diff --git a/src/features/diagnosticsProvider.ts b/src/features/diagnosticsProvider.ts
index 136c99776..8e910173b 100644
--- a/src/features/diagnosticsProvider.ts
+++ b/src/features/diagnosticsProvider.ts
@@ -140,7 +140,7 @@ class DiagnosticsProvider extends AbstractSupport {
         // Go ahead and check for diagnostics in the currently visible editors.
         for (let editor of vscode.window.visibleTextEditors) {
             let document = editor.document;
-            if (document.languageId === 'csharp' && document.uri.scheme === 'file') {
+            if (document.languageId === 'csharp') {
                 this._validateDocument(document);
             }
         }
@@ -172,7 +172,7 @@ class DiagnosticsProvider extends AbstractSupport {
     }
 
     private _onDocumentAddOrChange(document: vscode.TextDocument): void {
-        if (document.languageId === 'csharp' && document.uri.scheme === 'file') {
+        if (document.languageId === 'csharp') {
             this._validateDocument(document);
             this._validateProject();
         }
diff --git a/src/features/virtualDocumentTracker.ts b/src/features/virtualDocumentTracker.ts
new file mode 100644
index 000000000..e91b6ebdb
--- /dev/null
+++ b/src/features/virtualDocumentTracker.ts
@@ -0,0 +1,91 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import {workspace, TextDocument} from 'vscode';
+import {OmniSharpServer} from '../omnisharp/server';
+import * as serverUtils from '../omnisharp/utils';
+import { FileChangeType } from '../omnisharp/protocol';
+import { IDisposable } from '../Disposable';
+import CompositeDisposable from '../CompositeDisposable';
+
+function trackCurrentVirtualDocuments(server: OmniSharpServer) {
+    let registration = server.onProjectAdded(() => {
+        for (let i = 0; i < workspace.textDocuments.length; i++) {
+            let document = workspace.textDocuments[i];
+    
+            if (!shouldIgnoreDocument(document, server)) {
+                openVirtualDocument(document, server);
+            }
+        }
+
+        registration.dispose();
+    });
+}
+
+function trackFutureVirtualDocuments(server: OmniSharpServer): IDisposable {
+    let onTextDocumentOpen = workspace.onDidOpenTextDocument(document => {
+        if (shouldIgnoreDocument(document, server)) {
+            return;
+        }
+
+        openVirtualDocument(document, server);
+    });
+
+    let onTextDocumentClose = workspace.onDidCloseTextDocument(document => {
+        if (shouldIgnoreDocument(document, server)) {
+            return;
+        }
+
+        closeVirtualDocument(document, server);
+    });
+    
+    // We already track text document changes for virtual documents in our change forwarder.
+    return new CompositeDisposable(
+        onTextDocumentOpen,
+        onTextDocumentClose);
+}
+
+function shouldIgnoreDocument(document: TextDocument, server: OmniSharpServer): boolean {
+    if (document.uri.scheme === 'file' || document.languageId !== 'csharp') {
+        // We're only interested in non-physical CSharp documents.
+        return true;
+    }
+
+    if (!server.isRunning()) {
+        return true;
+    }
+
+    return false;
+}
+
+function openVirtualDocument(document: TextDocument, server: OmniSharpServer) {
+    let req = { FileName: document.uri.path, changeType: FileChangeType.Create };
+    serverUtils.filesChanged(server, [req])
+        .catch(err => {
+            console.warn(`[o] failed to forward virtual document change event for ${document.uri.path}`, err);
+            return err;
+        });
+
+    serverUtils.updateBuffer(server, { Buffer: document.getText(), FileName: document.fileName })
+        .catch(err => {
+            console.warn(`[o] failed to forward virtual document change event for ${document.uri.path}`, err);
+            return err;
+        });
+}
+
+function closeVirtualDocument(document: TextDocument, server: OmniSharpServer) {
+    let req = { FileName: document.uri.path, changeType: FileChangeType.Delete };
+    serverUtils.filesChanged(server, [req]).catch(err => {
+        console.warn(`[o] failed to forward virtual document change event for ${document.uri.path}`, err);
+        return err;
+    });
+}
+
+export default function trackVirtualDocuments(server: OmniSharpServer): IDisposable {
+    trackCurrentVirtualDocuments(server);
+    let disposable = trackFutureVirtualDocuments(server);
+    
+    return disposable;
+}
diff --git a/src/omnisharp/extension.ts b/src/omnisharp/extension.ts
index d434514c0..7adfa6bb9 100644
--- a/src/omnisharp/extension.ts
+++ b/src/omnisharp/extension.ts
@@ -34,6 +34,7 @@ import { NetworkSettingsProvider } from '../NetworkSettings';
 import CompositeDisposable from '../CompositeDisposable';
 import Disposable from '../Disposable';
 import OptionProvider from '../observers/OptionProvider';
+import trackVirtualDocuments from '../features/virtualDocumentTracker';
 import { StructureProvider } from '../features/structureProvider';
 
 export let omnisharp: OmniSharpServer;
@@ -41,7 +42,6 @@ export let omnisharp: OmniSharpServer;
 export async function activate(context: vscode.ExtensionContext, packageJSON: any, platformInfo: PlatformInformation, provider: NetworkSettingsProvider, eventStream: EventStream, optionProvider: OptionProvider, extensionPath: string) {
     const documentSelector: vscode.DocumentSelector = {
         language: 'csharp',
-        scheme: 'file' // only files from disk
     };
 
     const options = optionProvider.GetLatestOptions();
@@ -81,6 +81,7 @@ export async function activate(context: vscode.ExtensionContext, packageJSON: an
         localDisposables.add(vscode.languages.registerCodeActionsProvider(documentSelector, codeActionProvider));
         localDisposables.add(reportDiagnostics(server, advisor));
         localDisposables.add(forwardChanges(server));
+        localDisposables.add(trackVirtualDocuments(server));
         localDisposables.add(vscode.languages.registerFoldingRangeProvider(documentSelector, new StructureProvider(server)));
     }));