diff --git a/src/extension-host/services/extension.service.ts b/src/extension-host/services/extension.service.ts
index 4a7dd81e8d..c0a5bf9668 100644
--- a/src/extension-host/services/extension.service.ts
+++ b/src/extension-host/services/extension.service.ts
@@ -611,7 +611,8 @@ function getExtensionUri(baseUri: string, extensionName: string, extensionVersio
  */
 function extractExtensionDetailsFromFileNames(fileUris: string[]): ExtensionIdentifier[] {
   return fileUris.map((fileUri: string) => {
-    const fileName = fileUri.split('/').pop();
+    // Splits by either a forward-slash or back-slash to support Windows as well
+    const fileName = fileUri.split(path.sep).pop();
     if (!fileName?.endsWith('.zip')) throw new Error(`Not a ZIP file: ${fileName}`);
     const lastDashIndex = fileName.lastIndexOf('_');
     const extensionName = fileName.substring(0, lastDashIndex);