diff --git a/src/vs/workbench/api/node/extHost.protocol.ts b/src/vs/workbench/api/node/extHost.protocol.ts
index 079fb3a64d8..a740addb675 100644
--- a/src/vs/workbench/api/node/extHost.protocol.ts
+++ b/src/vs/workbench/api/node/extHost.protocol.ts
@@ -59,6 +59,7 @@ export interface IWorkspaceData {
 }
 
 export interface IInitData {
+	commit: string;
 	parentPid: number;
 	environment: IEnvironment;
 	workspace: IWorkspaceData;
diff --git a/src/vs/workbench/node/extensionHostProcess.ts b/src/vs/workbench/node/extensionHostProcess.ts
index 200bebe6f84..ba0e95ec5cf 100644
--- a/src/vs/workbench/node/extensionHostProcess.ts
+++ b/src/vs/workbench/node/extensionHostProcess.ts
@@ -14,6 +14,7 @@ import { createConnection } from 'net';
 import { Event, filterEvent } from 'vs/base/common/event';
 import { createMessageOfType, MessageType, isMessageOfType } from 'vs/workbench/common/extensionHostProtocol';
 import * as nativeWatchdog from 'native-watchdog';
+import product from 'vs/platform/node/product';
 
 // With Electron 2.x and node.js 8.x the "natives" module
 // can cause a native crash (see https://github.com/nodejs/node/issues/19891 and
@@ -89,6 +90,16 @@ function connectToRenderer(protocol: IMessagePassingProtocol): Promise<IRenderer
 
 			const initData = <IInitData>JSON.parse(raw.toString());
 
+			const rendererCommit = initData.commit;
+			const myCommit = product.commit;
+
+			if (rendererCommit && myCommit) {
+				// Running in the built version where commits are defined
+				if (rendererCommit !== myCommit) {
+					exit(55);
+				}
+			}
+
 			// Print a console message when rejection isn't handled within N seconds. For details:
 			// see https://nodejs.org/api/process.html#process_event_unhandledrejection
 			// and https://nodejs.org/api/process.html#process_event_rejectionhandled
diff --git a/src/vs/workbench/services/extensions/electron-browser/extensionHost.ts b/src/vs/workbench/services/extensions/electron-browser/extensionHost.ts
index 42ad8497c4d..a9017211fdc 100644
--- a/src/vs/workbench/services/extensions/electron-browser/extensionHost.ts
+++ b/src/vs/workbench/services/extensions/electron-browser/extensionHost.ts
@@ -385,6 +385,7 @@ export class ExtensionHostProcessWorker implements IExtensionHostStarter {
 				const configurationData: IConfigurationInitData = { ...this._configurationService.getConfigurationData(), configurationScopes: {} };
 				const workspace = this._contextService.getWorkspace();
 				const r: IInitData = {
+					commit: product.commit,
 					parentPid: process.pid,
 					environment: {
 						isExtensionDevelopmentDebug: this._isExtensionDevDebug,
diff --git a/src/vs/workbench/services/extensions/electron-browser/extensionService.ts b/src/vs/workbench/services/extensions/electron-browser/extensionService.ts
index 9547b706fcf..de147469de0 100644
--- a/src/vs/workbench/services/extensions/electron-browser/extensionService.ts
+++ b/src/vs/workbench/services/extensions/electron-browser/extensionService.ts
@@ -30,7 +30,7 @@ import { IInstantiationService } from 'vs/platform/instantiation/common/instanti
 import { ExtensionHostProcessWorker, IExtensionHostStarter } from 'vs/workbench/services/extensions/electron-browser/extensionHost';
 import { IMessagePassingProtocol } from 'vs/base/parts/ipc/node/ipc';
 import { ExtHostCustomersRegistry } from 'vs/workbench/api/electron-browser/extHostCustomers';
-import { IWindowService } from 'vs/platform/windows/common/windows';
+import { IWindowService, IWindowsService } from 'vs/platform/windows/common/windows';
 import { IDisposable, Disposable } from 'vs/base/common/lifecycle';
 import { mark } from 'vs/base/common/performance';
 import { ILifecycleService, LifecyclePhase } from 'vs/platform/lifecycle/common/lifecycle';
@@ -403,6 +403,23 @@ export class ExtensionService extends Disposable implements IExtensionService {
 		console.error('Extension host terminated unexpectedly. Code: ', code, ' Signal: ', signal);
 		this._stopExtensionHostProcess();
 
+		if (code === 55) {
+			this._notificationService.prompt(
+				Severity.Error,
+				nls.localize('extensionHostProcess.versionMismatchCrash', "Extension host cannot start: version mismatch."),
+				[{
+					label: nls.localize('relaunch', "Relaunch VS Code"),
+					run: () => {
+						this._instantiationService.invokeFunction((accessor) => {
+							const windowsService = accessor.get(IWindowsService);
+							windowsService.relaunch({});
+						});
+					}
+				}]
+			);
+			return;
+		}
+
 		let message = nls.localize('extensionHostProcess.crash', "Extension host terminated unexpectedly.");
 		if (code === 87) {
 			message = nls.localize('extensionHostProcess.unresponsiveCrash', "Extension host terminated because it was not responsive.");