diff --git a/src/vs/platform/windows/node/windowsIpc.ts b/src/vs/platform/windows/node/windowsIpc.ts
index dc10702ca5bdc2e1def9905ec03c8d6df1812849..408b73805177d3dc013cc30dafc2f5272fff24d0 100644
--- a/src/vs/platform/windows/node/windowsIpc.ts
+++ b/src/vs/platform/windows/node/windowsIpc.ts
@@ -6,7 +6,7 @@
 import { Event } from 'vs/base/common/event';
 import { IChannel, IServerChannel } from 'vs/base/parts/ipc/node/ipc';
 import { IWindowsService, INativeOpenDialogOptions, IEnterWorkspaceResult, CrashReporterStartOptions, IMessageBoxResult, MessageBoxOptions, SaveDialogOptions, OpenDialogOptions, IDevToolsOptions, INewWindowOptions } from 'vs/platform/windows/common/windows';
-import { IWorkspaceIdentifier, ISingleFolderWorkspaceIdentifier, isWorkspaceIdentifier } from 'vs/platform/workspaces/common/workspaces';
+import { IWorkspaceIdentifier, ISingleFolderWorkspaceIdentifier, isWorkspaceIdentifier, reviveWorkspaceIdentifier } from 'vs/platform/workspaces/common/workspaces';
 import { IRecentlyOpened } from 'vs/platform/history/common/history';
 import { ISerializableCommandAction } from 'vs/platform/actions/common/actions';
 import { URI } from 'vs/base/common/uri';
@@ -63,7 +63,7 @@ export class WindowsChannel implements IServerChannel {
 			case 'removeFromRecentlyOpened': {
 				let paths: Array<IWorkspaceIdentifier | ISingleFolderWorkspaceIdentifier | URI | string> = arg;
 				if (Array.isArray(paths)) {
-					paths = paths.map(path => isWorkspaceIdentifier(path) || typeof path === 'string' ? path : URI.revive(path));
+					paths = paths.map(path => isWorkspaceIdentifier(path) ? reviveWorkspaceIdentifier(path) : typeof path === 'string' ? path : URI.revive(path));
 				}
 				return this.service.removeFromRecentlyOpened(paths);
 			}
@@ -165,7 +165,9 @@ export class WindowsChannelClient implements IWindowsService {
 	}
 
 	enterWorkspace(windowId: number, path: URI): Promise<IEnterWorkspaceResult> {
-		return this.channel.call('enterWorkspace', [windowId, path]);
+		return this.channel.call('enterWorkspace', [windowId, path]).then((result: IEnterWorkspaceResult) => {
+			return { backupPath: result.backupPath, workspace: reviveWorkspaceIdentifier(result.workspace) };
+		});
 	}
 
 	toggleFullScreen(windowId: number): Promise<void> {
@@ -191,7 +193,7 @@ export class WindowsChannelClient implements IWindowsService {
 	getRecentlyOpened(windowId: number): Promise<IRecentlyOpened> {
 		return this.channel.call('getRecentlyOpened', windowId)
 			.then((recentlyOpened: IRecentlyOpened) => {
-				recentlyOpened.workspaces = recentlyOpened.workspaces.map(workspace => isWorkspaceIdentifier(workspace) ? workspace : URI.revive(workspace));
+				recentlyOpened.workspaces = recentlyOpened.workspaces.map(workspace => isWorkspaceIdentifier(workspace) ? reviveWorkspaceIdentifier(workspace) : URI.revive(workspace));
 				recentlyOpened.files = recentlyOpened.files.map(URI.revive);
 				return recentlyOpened;
 			});
@@ -286,7 +288,17 @@ export class WindowsChannelClient implements IWindowsService {
 	}
 
 	getWindows(): Promise<{ id: number; workspace?: IWorkspaceIdentifier; folderUri?: ISingleFolderWorkspaceIdentifier; title: string; filename?: string; }[]> {
-		return this.channel.call<{ id: number; workspace?: IWorkspaceIdentifier; folderUri?: ISingleFolderWorkspaceIdentifier; title: string; filename?: string; }[]>('getWindows').then(result => { result.forEach(win => win.folderUri = win.folderUri ? URI.revive(win.folderUri) : win.folderUri); return result; });
+		return this.channel.call<{ id: number; workspace?: IWorkspaceIdentifier; folderUri?: ISingleFolderWorkspaceIdentifier; title: string; filename?: string; }[]>('getWindows').then(result => {
+			for (const win of result) {
+				if (win.folderUri) {
+					win.folderUri = URI.revive(win.folderUri);
+				}
+				if (win.workspace) {
+					win.workspace = reviveWorkspaceIdentifier(win.workspace);
+				}
+			}
+			return result;
+		});
 	}
 
 	getWindowCount(): Promise<number> {
diff --git a/src/vs/platform/workspaces/common/workspaces.ts b/src/vs/platform/workspaces/common/workspaces.ts
index a5b8c5a57b8d68b93f8339c1926a4f8a786e4cd6..0b4c63729544e72ab281156bf3740f551006af89 100644
--- a/src/vs/platform/workspaces/common/workspaces.ts
+++ b/src/vs/platform/workspaces/common/workspaces.ts
@@ -7,7 +7,7 @@ import { createDecorator } from 'vs/platform/instantiation/common/instantiation'
 import { localize } from 'vs/nls';
 import { Event } from 'vs/base/common/event';
 import { IWorkspaceFolder, IWorkspace } from 'vs/platform/workspace/common/workspace';
-import { URI } from 'vs/base/common/uri';
+import { URI, UriComponents } from 'vs/base/common/uri';
 
 export const IWorkspacesMainService = createDecorator<IWorkspacesMainService>('workspacesMainService');
 export const IWorkspacesService = createDecorator<IWorkspacesService>('workspacesService');
@@ -26,6 +26,10 @@ export interface IWorkspaceIdentifier {
 	configPath: URI;
 }
 
+export function reviveWorkspaceIdentifier(workspace: { id: string, configPath: UriComponents; }) {
+	return { id: workspace.id, configPath: URI.revive(workspace.configPath) };
+}
+
 export function isStoredWorkspaceFolder(thing: any): thing is IStoredWorkspaceFolder {
 	return isRawFileWorkspaceFolder(thing) || isRawUriWorkspaceFolder(thing);
 }
diff --git a/src/vs/platform/workspaces/node/workspacesIpc.ts b/src/vs/platform/workspaces/node/workspacesIpc.ts
index 6b44c1dedead58c8bf46b663fa47341c2082cd17..11ae4da17ec89c8e6d43da3f35506196e65f0f2b 100644
--- a/src/vs/platform/workspaces/node/workspacesIpc.ts
+++ b/src/vs/platform/workspaces/node/workspacesIpc.ts
@@ -4,7 +4,7 @@
  *--------------------------------------------------------------------------------------------*/
 
 import { IChannel, IServerChannel } from 'vs/base/parts/ipc/node/ipc';
-import { IWorkspacesService, IWorkspaceIdentifier, IWorkspaceFolderCreationData, IWorkspacesMainService } from 'vs/platform/workspaces/common/workspaces';
+import { IWorkspacesService, IWorkspaceIdentifier, IWorkspaceFolderCreationData, IWorkspacesMainService, reviveWorkspaceIdentifier } from 'vs/platform/workspaces/common/workspaces';
 import { URI } from 'vs/base/common/uri';
 import { Event } from 'vs/base/common/event';
 
@@ -45,6 +45,6 @@ export class WorkspacesChannelClient implements IWorkspacesService {
 	constructor(private channel: IChannel) { }
 
 	createUntitledWorkspace(folders?: IWorkspaceFolderCreationData[]): Promise<IWorkspaceIdentifier> {
-		return this.channel.call('createUntitledWorkspace', folders);
+		return this.channel.call('createUntitledWorkspace', folders).then(reviveWorkspaceIdentifier);
 	}
 }
diff --git a/src/vs/workbench/electron-browser/main.ts b/src/vs/workbench/electron-browser/main.ts
index 1e6333c73140137e6d0a10efcbe7356bad18fd4c..07a0e5022d3d41cd377f0d648c71bcd5948a0664 100644
--- a/src/vs/workbench/electron-browser/main.ts
+++ b/src/vs/workbench/electron-browser/main.ts
@@ -29,7 +29,7 @@ import { IUpdateService } from 'vs/platform/update/common/update';
 import { URLHandlerChannel, URLServiceChannelClient } from 'vs/platform/url/node/urlIpc';
 import { IURLService } from 'vs/platform/url/common/url';
 import { WorkspacesChannelClient } from 'vs/platform/workspaces/node/workspacesIpc';
-import { IWorkspacesService, ISingleFolderWorkspaceIdentifier, IWorkspaceInitializationPayload, IMultiFolderWorkspaceInitializationPayload, IEmptyWorkspaceInitializationPayload, ISingleFolderWorkspaceInitializationPayload } from 'vs/platform/workspaces/common/workspaces';
+import { IWorkspacesService, ISingleFolderWorkspaceIdentifier, IWorkspaceInitializationPayload, IMultiFolderWorkspaceInitializationPayload, IEmptyWorkspaceInitializationPayload, ISingleFolderWorkspaceInitializationPayload, reviveWorkspaceIdentifier } from 'vs/platform/workspaces/common/workspaces';
 import { createSpdLogService } from 'vs/platform/log/node/spdlogService';
 import * as fs from 'fs';
 import { ConsoleLogService, MultiplexLogService, ILogService } from 'vs/platform/log/common/log';
@@ -87,6 +87,9 @@ function revive(workbench: IWindowConfiguration) {
 	if (workbench.folderUri) {
 		workbench.folderUri = uri.revive(workbench.folderUri);
 	}
+	if (workbench.workspace) {
+		workbench.workspace = reviveWorkspaceIdentifier(workbench.workspace);
+	}
 
 	const filesToWaitPaths = workbench.filesToWait && workbench.filesToWait.paths;
 	[filesToWaitPaths, workbench.filesToOpen, workbench.filesToCreate, workbench.filesToDiff].forEach(paths => {