diff --git a/src/vs/platform/workspaces/common/workspaces.ts b/src/vs/platform/workspaces/common/workspaces.ts
index 24e011b7b1b0ac2030d66795933f094a44963a32..dea714503145ec84d9e1e11cde1ffdb3dab6856b 100644
--- a/src/vs/platform/workspaces/common/workspaces.ts
+++ b/src/vs/platform/workspaces/common/workspaces.ts
@@ -29,11 +29,6 @@ export const UNTITLED_WORKSPACE_NAME = 'workspace.json';
  */
 export type ISingleFolderWorkspaceIdentifier = string;
 
-/**
- * A single folder workspace identifier is just the folder URI
- */
-export type ISingleFolderWorkspaceIdentifier2 = URI;
-
 export interface IWorkspaceIdentifier {
 	id: string;
 	configPath: string;
@@ -142,10 +137,6 @@ export function isSingleFolderWorkspaceIdentifier(obj: any): obj is ISingleFolde
 	return typeof obj === 'string';
 }
 
-export function isSingleFolderWorkspaceIdentifier2(obj: any): obj is ISingleFolderWorkspaceIdentifier2 {
-	return obj instanceof URI;
-}
-
 export function isWorkspaceIdentifier(obj: any): obj is IWorkspaceIdentifier {
 	const workspaceIdentifier = obj as IWorkspaceIdentifier;
 
diff --git a/src/vs/workbench/services/configuration/node/configurationService.ts b/src/vs/workbench/services/configuration/node/configurationService.ts
index eb707b12545db923b9023eb9c405c8d5e7dbe60b..dfb8e25c3b0edb00cc7e445e0c0912c3af85f832 100644
--- a/src/vs/workbench/services/configuration/node/configurationService.ts
+++ b/src/vs/workbench/services/configuration/node/configurationService.ts
@@ -26,7 +26,7 @@ import { IWorkspaceConfigurationService, FOLDER_CONFIG_FOLDER_NAME, defaultSetti
 import { Registry } from 'vs/platform/registry/common/platform';
 import { IConfigurationNode, IConfigurationRegistry, Extensions, IConfigurationPropertySchema, allSettings, windowSettings, resourceSettings, applicationSettings } from 'vs/platform/configuration/common/configurationRegistry';
 import { createHash } from 'crypto';
-import { getWorkspaceLabel, IWorkspaceIdentifier, ISingleFolderWorkspaceIdentifier, isSingleFolderWorkspaceIdentifier, isWorkspaceIdentifier, IStoredWorkspaceFolder, isStoredWorkspaceFolder, IWorkspaceFolderCreationData, ISingleFolderWorkspaceIdentifier2, isSingleFolderWorkspaceIdentifier2 } from 'vs/platform/workspaces/common/workspaces';
+import { getWorkspaceLabel, IWorkspaceIdentifier, ISingleFolderWorkspaceIdentifier, isSingleFolderWorkspaceIdentifier, isWorkspaceIdentifier, IStoredWorkspaceFolder, isStoredWorkspaceFolder, IWorkspaceFolderCreationData } from 'vs/platform/workspaces/common/workspaces';
 import { IWindowConfiguration } from 'vs/platform/windows/common/windows';
 import { IExtensionService } from 'vs/workbench/services/extensions/common/extensions';
 import { ICommandService } from 'vs/platform/commands/common/commands';
@@ -301,7 +301,7 @@ export class WorkspaceService extends Disposable implements IWorkspaceConfigurat
 		return this._configuration.keys();
 	}
 
-	initialize(arg: IWorkspaceIdentifier | ISingleFolderWorkspaceIdentifier2 | IWindowConfiguration, postInitialisationTask: () => void = () => null): TPromise<any> {
+	initialize(arg: IWorkspaceIdentifier | URI | IWindowConfiguration, postInitialisationTask: () => void = () => null): TPromise<any> {
 		return this.createWorkspace(arg)
 			.then(workspace => this.updateWorkspaceAndInitializeConfiguration(workspace, postInitialisationTask));
 	}
@@ -328,12 +328,12 @@ export class WorkspaceService extends Disposable implements IWorkspaceConfigurat
 		this.jsonEditingService = instantiationService.createInstance(JSONEditingService);
 	}
 
-	private createWorkspace(arg: IWorkspaceIdentifier | ISingleFolderWorkspaceIdentifier2 | IWindowConfiguration): TPromise<Workspace> {
+	private createWorkspace(arg: IWorkspaceIdentifier | URI | IWindowConfiguration): TPromise<Workspace> {
 		if (isWorkspaceIdentifier(arg)) {
 			return this.createMulitFolderWorkspace(arg);
 		}
 
-		if (isSingleFolderWorkspaceIdentifier2(arg)) {
+		if (arg instanceof URI) {
 			return this.createSingleFolderWorkspace(arg);
 		}
 
@@ -351,7 +351,7 @@ export class WorkspaceService extends Disposable implements IWorkspaceConfigurat
 			});
 	}
 
-	private createSingleFolderWorkspace(folder: ISingleFolderWorkspaceIdentifier2): TPromise<Workspace> {
+	private createSingleFolderWorkspace(folder: URI): TPromise<Workspace> {
 		if (folder.scheme === Schemas.file) {
 			return stat(folder.fsPath)
 				.then(workspaceStat => {