diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index dd71877930a62..8175730159b0b 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -1127,6 +1127,18 @@ namespace ts {
         };
     }
 
+    export function createCompilerDiagnosticFromMessageChain(chain: DiagnosticMessageChain): Diagnostic {
+        return {
+            file: undefined,
+            start: undefined,
+            length: undefined,
+
+            code: chain.code,
+            category: chain.category,
+            messageText: chain.next ? chain : chain.messageText
+        };
+    }
+
     export function chainDiagnosticMessages(details: DiagnosticMessageChain, message: DiagnosticMessage, ...args: any[]): DiagnosticMessageChain;
     export function chainDiagnosticMessages(details: DiagnosticMessageChain, message: DiagnosticMessage): DiagnosticMessageChain {
         let text = getLocaleSpecificMessage(message);
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 5290782c156a2..9a353e6fb3651 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -3158,5 +3158,9 @@
     "Implement inherited abstract class": {
         "category": "Message",
         "code": 90007
+    },
+    "Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig": {
+        "category": "Error",
+        "code": 90009
     }
 }
diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index 82d274e0487df..dcb9cce0adb55 100644
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -239,11 +239,11 @@ namespace ts {
                 const { line, character } = getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start);
                 const fileName = diagnostic.file.fileName;
                 const relativeFileName = convertToRelativePath(fileName, host.getCurrentDirectory(), fileName => host.getCanonicalFileName(fileName));
-                output += `${ relativeFileName }(${ line + 1 },${ character + 1 }): `;
+                output += `${relativeFileName}(${line + 1},${character + 1}): `;
             }
 
             const category = DiagnosticCategory[diagnostic.category].toLowerCase();
-            output += `${ category } TS${ diagnostic.code }: ${ flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) }${ host.getNewLine() }`;
+            output += `${category} TS${diagnostic.code}: ${flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine())}${host.getNewLine()}`;
         }
         return output;
     }
@@ -1685,13 +1685,24 @@ namespace ts {
                     const emitFilePath = toPath(emitFileName, currentDirectory, getCanonicalFileName);
                     // Report error if the output overwrites input file
                     if (filesByName.contains(emitFilePath)) {
-                        createEmitBlockingDiagnostics(emitFileName, Diagnostics.Cannot_write_file_0_because_it_would_overwrite_input_file);
+                        if (options.noEmitOverwritenFiles && !options.out && !options.outDir && !options.outFile) {
+                            blockEmittingOfFile(emitFileName);
+                        }
+                        else {
+                            let chain: DiagnosticMessageChain;
+                            if (!options.configFilePath) {
+                                // The program is from either an inferred project or an external project
+                                chain = chainDiagnosticMessages(/*details*/ undefined, Diagnostics.Adding_a_tsconfig_json_file_will_help_organize_projects_that_contain_both_TypeScript_and_JavaScript_files_Learn_more_at_https_Colon_Slash_Slashaka_ms_Slashtsconfig);
+                            }
+                            chain = chainDiagnosticMessages(chain, Diagnostics.Cannot_write_file_0_because_it_would_overwrite_input_file, emitFileName);
+                            blockEmittingOfFile(emitFileName, createCompilerDiagnosticFromMessageChain(chain));
+                        }
                     }
 
                     // Report error if multiple files write into same file
                     if (emitFilesSeen.contains(emitFilePath)) {
                         // Already seen the same emit file - report error
-                        createEmitBlockingDiagnostics(emitFileName, Diagnostics.Cannot_write_file_0_because_it_would_be_overwritten_by_multiple_input_files);
+                        blockEmittingOfFile(emitFileName, createCompilerDiagnostic(Diagnostics.Cannot_write_file_0_because_it_would_be_overwritten_by_multiple_input_files, emitFileName));
                     }
                     else {
                         emitFilesSeen.set(emitFilePath, true);
@@ -1700,9 +1711,11 @@ namespace ts {
             }
         }
 
-        function createEmitBlockingDiagnostics(emitFileName: string, message: DiagnosticMessage) {
+        function blockEmittingOfFile(emitFileName: string, diag?: Diagnostic) {
             hasEmitBlockingDiagnostics.set(toPath(emitFileName, currentDirectory, getCanonicalFileName), true);
-            programDiagnostics.add(createCompilerDiagnostic(message, emitFileName));
+            if (diag) {
+                programDiagnostics.add(diag);
+            }
         }
     }
 
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index b865beca76b9a..5536a818df536 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -3058,6 +3058,7 @@ namespace ts {
         moduleResolution?: ModuleResolutionKind;
         newLine?: NewLineKind;
         noEmit?: boolean;
+        /*@internal*/noEmitOverwritenFiles?: boolean;
         noEmitHelpers?: boolean;
         noEmitOnError?: boolean;
         noErrorTruncation?: boolean;
diff --git a/src/harness/fourslash.ts b/src/harness/fourslash.ts
index b008ca653702d..ae32fe3db1631 100644
--- a/src/harness/fourslash.ts
+++ b/src/harness/fourslash.ts
@@ -1253,7 +1253,18 @@ namespace FourSlash {
                             resultString += "Diagnostics:" + Harness.IO.newLine();
                             const diagnostics = ts.getPreEmitDiagnostics(this.languageService.getProgram());
                             for (const diagnostic of diagnostics) {
-                                resultString += "  " + diagnostic.messageText + Harness.IO.newLine();
+                                if (typeof diagnostic.messageText !== "string") {
+                                    let chainedMessage = <ts.DiagnosticMessageChain>diagnostic.messageText;
+                                    let indentation = " ";
+                                    while (chainedMessage) {
+                                        resultString += indentation + chainedMessage.messageText + Harness.IO.newLine();
+                                        chainedMessage = chainedMessage.next;
+                                        indentation = indentation + " ";
+                                    }
+                                }
+                                else {
+                                    resultString += "  " + diagnostic.messageText + Harness.IO.newLine();
+                                }
                             }
                         }
 
diff --git a/src/harness/unittests/tsserverProjectSystem.ts b/src/harness/unittests/tsserverProjectSystem.ts
index 870926a8c5595..15cfa3f8c8e7c 100644
--- a/src/harness/unittests/tsserverProjectSystem.ts
+++ b/src/harness/unittests/tsserverProjectSystem.ts
@@ -2505,4 +2505,28 @@ namespace ts.projectSystem {
             checkProjectActualFiles(projectService.inferredProjects[0], [f.path]);
         });
     });
+
+    describe("No overwrite emit error", () => {
+        it("for inferred project", () => {
+            const f1 = {
+                path: "/a/b/f1.js",
+                content: "function test1() { }"
+            };
+            const host = createServerHost([f1, libFile]);
+            const session = createSession(host);
+            openFilesForSession([f1], session);
+
+            const projectService = session.getProjectService();
+            checkNumberOfProjects(projectService, { inferredProjects: 1 });
+            const projectName = projectService.inferredProjects[0].getProjectName();
+
+            const diags = session.executeCommand(<server.protocol.CompilerOptionsDiagnosticsRequest>{
+                type: "request",
+                command: server.CommandNames.CompilerOptionsDiagnosticsFull,
+                seq: 2,
+                arguments: { projectFileName: projectName }
+            }).response;
+            assert.isTrue(diags.length === 0);
+        });
+    });
 }
\ No newline at end of file
diff --git a/src/server/project.ts b/src/server/project.ts
index 457f5e2b261df..563b045691071 100644
--- a/src/server/project.ts
+++ b/src/server/project.ts
@@ -161,6 +161,10 @@ namespace ts.server {
                 this.compilerOptions.allowNonTsExtensions = true;
             }
 
+            if (this.projectKind === ProjectKind.Inferred) {
+                this.compilerOptions.noEmitOverwritenFiles = true;
+            }
+
             if (languageServiceEnabled) {
                 this.enableLanguageService();
             }
diff --git a/tests/baselines/reference/compileOnSaveWorksWhenEmitBlockingErrorOnOtherFile.baseline b/tests/baselines/reference/compileOnSaveWorksWhenEmitBlockingErrorOnOtherFile.baseline
index a088006d1450e..f8b479e6d7b7b 100644
--- a/tests/baselines/reference/compileOnSaveWorksWhenEmitBlockingErrorOnOtherFile.baseline
+++ b/tests/baselines/reference/compileOnSaveWorksWhenEmitBlockingErrorOnOtherFile.baseline
@@ -1,6 +1,7 @@
 EmitSkipped: true
 Diagnostics:
-  Cannot write file '/tests/cases/fourslash/b.js' because it would overwrite input file.
+ Cannot write file '/tests/cases/fourslash/b.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 EmitSkipped: false
 FileName : /tests/cases/fourslash/a.js
diff --git a/tests/baselines/reference/declarationFileOverwriteError.errors.txt b/tests/baselines/reference/declarationFileOverwriteError.errors.txt
index 1974976dee1fe..211469778b1fe 100644
--- a/tests/baselines/reference/declarationFileOverwriteError.errors.txt
+++ b/tests/baselines/reference/declarationFileOverwriteError.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.d.ts' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.d.ts' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.d.ts (0 errors) ====
     
     declare class c {
diff --git a/tests/baselines/reference/declarationFileOverwriteErrorWithOut.errors.txt b/tests/baselines/reference/declarationFileOverwriteErrorWithOut.errors.txt
index 658465de9c2d2..ea4a93b3b12db 100644
--- a/tests/baselines/reference/declarationFileOverwriteErrorWithOut.errors.txt
+++ b/tests/baselines/reference/declarationFileOverwriteErrorWithOut.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/compiler/out.d.ts' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/out.d.ts' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/out.d.ts (0 errors) ====
     
     declare class c {
diff --git a/tests/baselines/reference/exportDefaultInJsFile01.errors.txt b/tests/baselines/reference/exportDefaultInJsFile01.errors.txt
index 34035e1e14e73..0565c8bd61ef2 100644
--- a/tests/baselines/reference/exportDefaultInJsFile01.errors.txt
+++ b/tests/baselines/reference/exportDefaultInJsFile01.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/conformance/salsa/myFile01.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/conformance/salsa/myFile01.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/conformance/salsa/myFile01.js (0 errors) ====
     
     export default "hello";
\ No newline at end of file
diff --git a/tests/baselines/reference/exportDefaultInJsFile02.errors.txt b/tests/baselines/reference/exportDefaultInJsFile02.errors.txt
index 5e17306e066f5..a74fbacfcfd87 100644
--- a/tests/baselines/reference/exportDefaultInJsFile02.errors.txt
+++ b/tests/baselines/reference/exportDefaultInJsFile02.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/conformance/salsa/myFile02.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/conformance/salsa/myFile02.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/conformance/salsa/myFile02.js (0 errors) ====
     
     export default "hello";
\ No newline at end of file
diff --git a/tests/baselines/reference/jsFileCompilationAmbientVarDeclarationSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationAmbientVarDeclarationSyntax.errors.txt
index 19bfd5d1c0205..039834ff702af 100644
--- a/tests/baselines/reference/jsFileCompilationAmbientVarDeclarationSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationAmbientVarDeclarationSyntax.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,1): error TS8009: 'declare' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     declare var v;
     ~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationEmitBlockedCorrectly.errors.txt b/tests/baselines/reference/jsFileCompilationEmitBlockedCorrectly.errors.txt
index 0aa9d5733d532..75bcf88b10a13 100644
--- a/tests/baselines/reference/jsFileCompilationEmitBlockedCorrectly.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationEmitBlockedCorrectly.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 !!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
diff --git a/tests/baselines/reference/jsFileCompilationEnumSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationEnumSyntax.errors.txt
index 538dfb38972bc..c6da8931d5e3e 100644
--- a/tests/baselines/reference/jsFileCompilationEnumSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationEnumSyntax.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,6): error TS8015: 'enum declarations' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     enum E { }
          ~
diff --git a/tests/baselines/reference/jsFileCompilationErrorOnDeclarationsWithJsFileReferenceWithNoOut.errors.txt b/tests/baselines/reference/jsFileCompilationErrorOnDeclarationsWithJsFileReferenceWithNoOut.errors.txt
index 641731936f84a..54e91c5d1961e 100644
--- a/tests/baselines/reference/jsFileCompilationErrorOnDeclarationsWithJsFileReferenceWithNoOut.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationErrorOnDeclarationsWithJsFileReferenceWithNoOut.errors.txt
@@ -1,9 +1,11 @@
 error TS5053: Option 'allowJs' cannot be specified with option 'declaration'.
 error TS5055: Cannot write file 'tests/cases/compiler/c.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5053: Option 'allowJs' cannot be specified with option 'declaration'.
 !!! error TS5055: Cannot write file 'tests/cases/compiler/c.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationExportAssignmentSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationExportAssignmentSyntax.errors.txt
index f537941c55cf1..babbeea800455 100644
--- a/tests/baselines/reference/jsFileCompilationExportAssignmentSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationExportAssignmentSyntax.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,1): error TS8003: 'export=' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     export = b;
     ~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationHeritageClauseSyntaxOfClass.errors.txt b/tests/baselines/reference/jsFileCompilationHeritageClauseSyntaxOfClass.errors.txt
index 33b8a45f1aab0..3b30663308fa5 100644
--- a/tests/baselines/reference/jsFileCompilationHeritageClauseSyntaxOfClass.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationHeritageClauseSyntaxOfClass.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,9): error TS8005: 'implements clauses' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C implements D { }
             ~~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationImportEqualsSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationImportEqualsSyntax.errors.txt
index b416136703755..a064f53e92fa4 100644
--- a/tests/baselines/reference/jsFileCompilationImportEqualsSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationImportEqualsSyntax.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,1): error TS8002: 'import ... =' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     import a = b;
     ~~~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationInterfaceSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationInterfaceSyntax.errors.txt
index 17fb8fcb18741..9e53438c732fd 100644
--- a/tests/baselines/reference/jsFileCompilationInterfaceSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationInterfaceSyntax.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,11): error TS8006: 'interface declarations' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     interface I { }
               ~
diff --git a/tests/baselines/reference/jsFileCompilationModuleSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationModuleSyntax.errors.txt
index 662028c53ed93..6952c0055c0ee 100644
--- a/tests/baselines/reference/jsFileCompilationModuleSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationModuleSyntax.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,8): error TS8007: 'module declarations' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     module M { }
            ~
diff --git a/tests/baselines/reference/jsFileCompilationNoErrorWithoutDeclarationsWithJsFileReferenceWithNoOut.errors.txt b/tests/baselines/reference/jsFileCompilationNoErrorWithoutDeclarationsWithJsFileReferenceWithNoOut.errors.txt
index f2f4142b99380..888310414f275 100644
--- a/tests/baselines/reference/jsFileCompilationNoErrorWithoutDeclarationsWithJsFileReferenceWithNoOut.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationNoErrorWithoutDeclarationsWithJsFileReferenceWithNoOut.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/compiler/c.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/c.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationOptionalParameter.errors.txt b/tests/baselines/reference/jsFileCompilationOptionalParameter.errors.txt
index 295f827dd2d7c..15bfe2281d96f 100644
--- a/tests/baselines/reference/jsFileCompilationOptionalParameter.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationOptionalParameter.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,13): error TS8009: '?' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     function F(p?) { }
                 ~
diff --git a/tests/baselines/reference/jsFileCompilationPublicMethodSyntaxOfClass.errors.txt b/tests/baselines/reference/jsFileCompilationPublicMethodSyntaxOfClass.errors.txt
index d67c9baea70e5..af95c13620559 100644
--- a/tests/baselines/reference/jsFileCompilationPublicMethodSyntaxOfClass.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationPublicMethodSyntaxOfClass.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(2,5): error TS8009: 'public' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C {
         public foo() {
diff --git a/tests/baselines/reference/jsFileCompilationPublicParameterModifier.errors.txt b/tests/baselines/reference/jsFileCompilationPublicParameterModifier.errors.txt
index bc4913f6217b4..9314e1da807aa 100644
--- a/tests/baselines/reference/jsFileCompilationPublicParameterModifier.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationPublicParameterModifier.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,23): error TS8012: 'parameter modifiers' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C { constructor(public x) { }}
                           ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationReturnTypeSyntaxOfFunction.errors.txt b/tests/baselines/reference/jsFileCompilationReturnTypeSyntaxOfFunction.errors.txt
index 6dad5a294854c..acae950d0816a 100644
--- a/tests/baselines/reference/jsFileCompilationReturnTypeSyntaxOfFunction.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationReturnTypeSyntaxOfFunction.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,15): error TS8010: 'types' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     function F(): number { }
                   ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationSyntaxError.errors.txt b/tests/baselines/reference/jsFileCompilationSyntaxError.errors.txt
index d98a1e7e7bbc8..eb4c114d3d074 100644
--- a/tests/baselines/reference/jsFileCompilationSyntaxError.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationSyntaxError.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (0 errors) ====
     /**
       * @type {number}
diff --git a/tests/baselines/reference/jsFileCompilationTypeAliasSyntax.errors.txt b/tests/baselines/reference/jsFileCompilationTypeAliasSyntax.errors.txt
index 2b5112e1ce2ed..74978eddf8ce1 100644
--- a/tests/baselines/reference/jsFileCompilationTypeAliasSyntax.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeAliasSyntax.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,6): error TS8008: 'type aliases' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     type a = b;
          ~
diff --git a/tests/baselines/reference/jsFileCompilationTypeArgumentSyntaxOfCall.errors.txt b/tests/baselines/reference/jsFileCompilationTypeArgumentSyntaxOfCall.errors.txt
index 8ac59196ed960..f53ec55d2b1e0 100644
--- a/tests/baselines/reference/jsFileCompilationTypeArgumentSyntaxOfCall.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeArgumentSyntaxOfCall.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,5): error TS8011: 'type arguments' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     Foo<number>();
         ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationTypeAssertions.errors.txt b/tests/baselines/reference/jsFileCompilationTypeAssertions.errors.txt
index 662eea4d4050c..be1e6d3243699 100644
--- a/tests/baselines/reference/jsFileCompilationTypeAssertions.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeAssertions.errors.txt
@@ -1,9 +1,11 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,10): error TS17008: JSX element 'string' has no corresponding closing tag.
 tests/cases/compiler/a.js(1,27): error TS1005: '</' expected.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (2 errors) ====
     var v = <string>undefined;
              ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationTypeOfParameter.errors.txt b/tests/baselines/reference/jsFileCompilationTypeOfParameter.errors.txt
index 680b32a64f1ad..811c0793ffe15 100644
--- a/tests/baselines/reference/jsFileCompilationTypeOfParameter.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeOfParameter.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,15): error TS8010: 'types' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     function F(a: number) { }
                   ~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfClass.errors.txt b/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfClass.errors.txt
index 161c832ffd5d4..0fe902aa661cb 100644
--- a/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfClass.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfClass.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,9): error TS8004: 'type parameter declarations' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     class C<T> { }
             ~
diff --git a/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfFunction.errors.txt b/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfFunction.errors.txt
index d7626f68564cf..bfc4c7be26a4d 100644
--- a/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfFunction.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeParameterSyntaxOfFunction.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,12): error TS8004: 'type parameter declarations' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     function F<T>() { }
                ~
diff --git a/tests/baselines/reference/jsFileCompilationTypeSyntaxOfVar.errors.txt b/tests/baselines/reference/jsFileCompilationTypeSyntaxOfVar.errors.txt
index 2c6ac3771bef8..653337517800b 100644
--- a/tests/baselines/reference/jsFileCompilationTypeSyntaxOfVar.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationTypeSyntaxOfVar.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 tests/cases/compiler/a.js(1,8): error TS8010: 'types' can only be used in a .ts file.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.js (1 errors) ====
     var v: () => number;
            ~~~~~~~~~~~~
diff --git a/tests/baselines/reference/jsFileCompilationWithDeclarationEmitPathSameAsInput.errors.txt b/tests/baselines/reference/jsFileCompilationWithDeclarationEmitPathSameAsInput.errors.txt
index 9e9c2adb0efa2..4170e818fd76b 100644
--- a/tests/baselines/reference/jsFileCompilationWithDeclarationEmitPathSameAsInput.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithDeclarationEmitPathSameAsInput.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.d.ts' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.d.ts' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationWithJsEmitPathSameAsInput.errors.txt b/tests/baselines/reference/jsFileCompilationWithJsEmitPathSameAsInput.errors.txt
index 4cc2cc2ab4547..8004efd02eff4 100644
--- a/tests/baselines/reference/jsFileCompilationWithJsEmitPathSameAsInput.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithJsEmitPathSameAsInput.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 !!! error TS5056: Cannot write file 'tests/cases/compiler/a.js' because it would be overwritten by multiple input files.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
diff --git a/tests/baselines/reference/jsFileCompilationWithMapFileAsJs.errors.txt b/tests/baselines/reference/jsFileCompilationWithMapFileAsJs.errors.txt
index 06186b9f0b2fc..069c562f29bf8 100644
--- a/tests/baselines/reference/jsFileCompilationWithMapFileAsJs.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithMapFileAsJs.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 error TS6054: File 'tests/cases/compiler/b.js.map' has unsupported extension. The only supported extensions are '.ts', '.tsx', '.d.ts', '.js', '.jsx'.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 !!! error TS6054: File 'tests/cases/compiler/b.js.map' has unsupported extension. The only supported extensions are '.ts', '.tsx', '.d.ts', '.js', '.jsx'.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     
diff --git a/tests/baselines/reference/jsFileCompilationWithMapFileAsJsWithInlineSourceMap.errors.txt b/tests/baselines/reference/jsFileCompilationWithMapFileAsJsWithInlineSourceMap.errors.txt
index 06186b9f0b2fc..069c562f29bf8 100644
--- a/tests/baselines/reference/jsFileCompilationWithMapFileAsJsWithInlineSourceMap.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithMapFileAsJsWithInlineSourceMap.errors.txt
@@ -1,8 +1,10 @@
 error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 error TS6054: File 'tests/cases/compiler/b.js.map' has unsupported extension. The only supported extensions are '.ts', '.tsx', '.d.ts', '.js', '.jsx'.
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 !!! error TS6054: File 'tests/cases/compiler/b.js.map' has unsupported extension. The only supported extensions are '.ts', '.tsx', '.d.ts', '.js', '.jsx'.
 ==== tests/cases/compiler/a.ts (0 errors) ====
     
diff --git a/tests/baselines/reference/jsFileCompilationWithOutDeclarationFileNameSameAsInputJsFile.errors.txt b/tests/baselines/reference/jsFileCompilationWithOutDeclarationFileNameSameAsInputJsFile.errors.txt
index 10c7b8c90ddad..0a4f0cdf1a45b 100644
--- a/tests/baselines/reference/jsFileCompilationWithOutDeclarationFileNameSameAsInputJsFile.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithOutDeclarationFileNameSameAsInputJsFile.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/compiler/b.d.ts' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/b.d.ts' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationWithOutFileNameSameAsInputJsFile.errors.txt b/tests/baselines/reference/jsFileCompilationWithOutFileNameSameAsInputJsFile.errors.txt
index 0f6852b21a0a2..3f72a8113ef2c 100644
--- a/tests/baselines/reference/jsFileCompilationWithOutFileNameSameAsInputJsFile.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithOutFileNameSameAsInputJsFile.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/jsFileCompilationWithoutOut.errors.txt b/tests/baselines/reference/jsFileCompilationWithoutOut.errors.txt
index 0f6852b21a0a2..3f72a8113ef2c 100644
--- a/tests/baselines/reference/jsFileCompilationWithoutOut.errors.txt
+++ b/tests/baselines/reference/jsFileCompilationWithoutOut.errors.txt
@@ -1,7 +1,9 @@
 error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5055: Cannot write file 'tests/cases/compiler/b.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== tests/cases/compiler/a.ts (0 errors) ====
     class c {
     }
diff --git a/tests/baselines/reference/project/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs/amd/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs.errors.txt b/tests/baselines/reference/project/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs/amd/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs.errors.txt
index ac25edc1bd565..668f037a03b4d 100644
--- a/tests/baselines/reference/project/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs/amd/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs.errors.txt
+++ b/tests/baselines/reference/project/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs/amd/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs.errors.txt
@@ -1,9 +1,11 @@
 error TS5053: Option 'allowJs' cannot be specified with option 'declaration'.
 error TS5055: Cannot write file 'SameNameDTsNotSpecifiedWithAllowJs/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5053: Option 'allowJs' cannot be specified with option 'declaration'.
 !!! error TS5055: Cannot write file 'SameNameDTsNotSpecifiedWithAllowJs/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== SameNameDTsNotSpecifiedWithAllowJs/a.d.ts (0 errors) ====
     declare var a: number;
 ==== SameNameDTsNotSpecifiedWithAllowJs/a.js (0 errors) ====
diff --git a/tests/baselines/reference/project/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs/node/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs.errors.txt b/tests/baselines/reference/project/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs/node/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs.errors.txt
index ac25edc1bd565..668f037a03b4d 100644
--- a/tests/baselines/reference/project/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs/node/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs.errors.txt
+++ b/tests/baselines/reference/project/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs/node/jsFileCompilationSameNameDtsNotSpecifiedWithAllowJs.errors.txt
@@ -1,9 +1,11 @@
 error TS5053: Option 'allowJs' cannot be specified with option 'declaration'.
 error TS5055: Cannot write file 'SameNameDTsNotSpecifiedWithAllowJs/a.js' because it would overwrite input file.
+  Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 
 
 !!! error TS5053: Option 'allowJs' cannot be specified with option 'declaration'.
 !!! error TS5055: Cannot write file 'SameNameDTsNotSpecifiedWithAllowJs/a.js' because it would overwrite input file.
+!!! error TS5055:   Adding a tsconfig.json file will help organize projects that contain both TypeScript and JavaScript files. Learn more at https://aka.ms/tsconfig
 ==== SameNameDTsNotSpecifiedWithAllowJs/a.d.ts (0 errors) ====
     declare var a: number;
 ==== SameNameDTsNotSpecifiedWithAllowJs/a.js (0 errors) ====