diff --git a/packages/core/src/browser/resource-context-key.ts b/packages/core/src/browser/resource-context-key.ts
index 31948c9070890..a1d0b89d2572d 100644
--- a/packages/core/src/browser/resource-context-key.ts
+++ b/packages/core/src/browser/resource-context-key.ts
@@ -19,6 +19,8 @@ import URI from '../common/uri';
 import { URI as Uri } from 'vscode-uri';
 import { ContextKeyService, ContextKey } from './context-key-service';
 import { LanguageService } from './language-service';
+import { ApplicationServer } from '../common/application-protocol';
+import { OS } from '../common/os';
 
 @injectable()
 export class ResourceContextKey {
@@ -29,6 +31,9 @@ export class ResourceContextKey {
     @inject(ContextKeyService)
     protected readonly contextKeyService: ContextKeyService;
 
+    @inject(ApplicationServer)
+    protected readonly applicationService: ApplicationServer;
+
     protected resource: ContextKey<Uri>;
     protected resourceSchemeKey: ContextKey<string>;
     protected resourceFileName: ContextKey<string>;
@@ -36,9 +41,10 @@ export class ResourceContextKey {
     protected resourceLangId: ContextKey<string>;
     protected resourceDirName: ContextKey<string>;
     protected resourcePath: ContextKey<string>;
+    protected isPosix: boolean;
 
     @postConstruct()
-    protected init(): void {
+    protected async init(): Promise<void> {
         this.resource = this.contextKeyService.createKey<Uri>('resource', undefined);
         this.resourceSchemeKey = this.contextKeyService.createKey<string>('resourceScheme', undefined);
         this.resourceFileName = this.contextKeyService.createKey<string>('resourceFilename', undefined);
@@ -46,6 +52,7 @@ export class ResourceContextKey {
         this.resourceLangId = this.contextKeyService.createKey<string>('resourceLangId', undefined);
         this.resourceDirName = this.contextKeyService.createKey<string>('resourceDirName', undefined);
         this.resourcePath = this.contextKeyService.createKey<string>('resourcePath', undefined);
+        this.isPosix = await this.applicationService.getBackendOS() !== OS.Type.Windows;
     }
 
     get(): URI | undefined {
@@ -59,8 +66,8 @@ export class ResourceContextKey {
         this.resourceFileName.set(resourceUri && resourceUri.path.base);
         this.resourceExtname.set(resourceUri && resourceUri.path.ext);
         this.resourceLangId.set(resourceUri && this.getLanguageId(resourceUri));
-        this.resourceDirName.set(resourceUri && Uri.parse(resourceUri.path.dir.toString()).fsPath);
-        this.resourcePath.set(resourceUri && resourceUri['codeUri'].fsPath);
+        this.resourceDirName.set(resourceUri && resourceUri.path.dir.fsPath(this.isPosix));
+        this.resourcePath.set(resourceUri && resourceUri.path.fsPath(this.isPosix));
     }
 
     protected getLanguageId(uri: URI | undefined): string | undefined {
diff --git a/packages/core/src/common/path.spec.ts b/packages/core/src/common/path.spec.ts
index cad2fa694323a..9ca3d7907e6ef 100644
--- a/packages/core/src/common/path.spec.ts
+++ b/packages/core/src/common/path.spec.ts
@@ -356,4 +356,60 @@ describe('Path', () => {
         });
 
     });
+
+    describe('fsPath#undefined', () => {
+        it('should retain windows style path', () => {
+            const path = 'C:\\path\\to\\file.txt';
+            expect(new Path(path).fsPath()).eq(path);
+        });
+
+        it('should create windows style path with slashes', () => {
+            const path = 'C:/path/to/file.txt';
+            const expected = 'C:\\path\\to\\file.txt';
+            expect(new Path(path).fsPath()).eq(expected);
+        });
+
+        it('should retain posix style path', () => {
+            const path = '/path/to/file.txt';
+            expect(new Path(path).fsPath()).eq(path);
+        });
+    });
+
+    describe('fsPath#windows', () => {
+        it('should retain windows style path', () => {
+            const path = 'C:\\path\\to\\file.txt';
+            expect(new Path(path).fsPath(false)).eq(path);
+        });
+
+        it('should create windows style path with slashes', () => {
+            const path = 'C:/path/to/file.txt';
+            const expected = 'C:\\path\\to\\file.txt';
+            expect(new Path(path).fsPath(false)).eq(expected);
+        });
+
+        it('should create windows style path from posix', () => {
+            const path = '/path/to/file.txt';
+            const expected = '\\path\\to\\file.txt';
+            expect(new Path(path).fsPath(false)).eq(expected);
+        });
+    });
+
+    describe('fsPath#posix', () => {
+        it('should retain posix style path', () => {
+            const path = '/path/to/file.txt';
+            expect(new Path(path).fsPath(true)).eq(path);
+        });
+
+        it('should create posix style path from windows with slashes', () => {
+            const path = 'C:/path/to/file.txt';
+            const expected = '/c:/path/to/file.txt';
+            expect(new Path(path).fsPath(true)).eq(expected);
+        });
+
+        it('should create posix style path from windows', () => {
+            const path = 'C:\\path\\to\\file.txt';
+            const expected = '/c:/path/to/file.txt';
+            expect(new Path(path).fsPath(true)).eq(expected);
+        });
+    });
 });
diff --git a/packages/core/src/common/path.ts b/packages/core/src/common/path.ts
index b2613bc31e164..54430b0c99f67 100644
--- a/packages/core/src/common/path.ts
+++ b/packages/core/src/common/path.ts
@@ -70,6 +70,35 @@ export class Path {
         return path.split(/[\\]/).join(Path.separator);
     }
 
+    /**
+     * Creates a windows path from the given path string.
+     * A windows path uses an upper case drive letter and backwards slashes.
+     * @param path The input path
+     * @returns Windows style path
+     */
+    static windowsPath(path: string): string {
+        const offset = path.charAt(0) === '/' ? 1 : 0;
+        if (path.charAt(offset + 2) === '/' && path.charAt(offset + 1) === ':') {
+            const driveLetter = path.charAt(offset).toUpperCase();
+            const substring = path.substring(offset + 1).replace(/\//g, '\\');
+            return `${driveLetter}${substring}`;
+        }
+        return path.replace(/\//g, '\\');
+    }
+
+    /**
+     * Creates a posix path from the given path string.
+     * A posix path always starts with a forward slash and contains only forward slashes.
+     * @param path The input path
+     * @returns A posix style path
+     */
+    static posixPath(path: string): string {
+        if (path.charAt(0) !== '/') {
+            path = '/' + path;
+        }
+        return path;
+    }
+
     /**
      * Tildify path, replacing `home` with `~` if user's `home` is present at the beginning of the path.
      * This is a non-operation for Windows.
@@ -206,6 +235,26 @@ export class Path {
         return this.raw;
     }
 
+    /**
+     * Converts the current path into a file system path.
+     * @param posix Indicates posix or windows file path.
+     * If `undefined`, the format will be determined by whether the raw path starts with a drive letter.
+     * @returns A file system path.
+     */
+    fsPath(posix?: boolean): string {
+        if (posix === undefined) {
+            if (this.raw.charAt(1) === ':' || this.raw.charAt(2) === ':') {
+                return Path.windowsPath(this.raw);
+            } else {
+                return Path.posixPath(this.raw);
+            }
+        } else if (posix) {
+            return Path.posixPath(this.raw);
+        } else {
+            return Path.windowsPath(this.raw);
+        }
+    }
+
     relative(path: Path): Path | undefined {
         if (this.raw === path.raw) {
             return new Path('');
diff --git a/packages/filesystem/src/browser/file-tree/file-tree-widget.tsx b/packages/filesystem/src/browser/file-tree/file-tree-widget.tsx
index 2300015220af4..52fc902f57745 100644
--- a/packages/filesystem/src/browser/file-tree/file-tree-widget.tsx
+++ b/packages/filesystem/src/browser/file-tree/file-tree-widget.tsx
@@ -100,7 +100,7 @@ export class FileTreeWidget extends TreeViewWelcomeWidget {
 
     protected getNodeTooltip(node: TreeNode): string | undefined {
         const uri = UriSelection.getUri(node);
-        return uri ? uri.path.toString() : undefined;
+        return uri ? uri.path.fsPath() : undefined;
     }
 
     protected handleDragStartEvent(node: TreeNode, event: React.DragEvent): void {