title: How to solve Microsoft.VisualStudio.ExtensionManager.MissingReferencesException
body: <p>I'm trying to make extension for VS2013 preview, here is my try on GitHub: <a href="https://github.com/Heather/Nemerle/tree/VS2013" rel="noreferrer">https://github.com/Heather/Nemerle/tree/VS2013</a></p>
  
  <p>But for now I'm getting:</p>
  
  <pre><code>07.08.2013 9:25:05 - The following target products have been selected...
  07.08.2013 9:25:05 -    Microsoft Visual Studio Ultimate 2013 Preview
  07.08.2013 9:25:05 - 
  07.08.2013 9:25:05 - Beginning to install extension to Microsoft Visual Studio Ultimate 2013 Preview...
  07.08.2013 9:25:05 - Install Error : Microsoft.VisualStudio.ExtensionManager.MissingReferencesException: This extension cannot be installed because the following references are missing:
  - Visual Studio MPF
     at Microsoft.VisualStudio.ExtensionManager.ExtensionManagerService.CheckForInstallBlockers(InstallableExtensionImpl extension, IInstalledExtensionList modifiedInstalledExtensionsList, Boolean isNestedExtension, Boolean&amp; olderVersionInstalled)
     at Microsoft.VisualStudio.ExtensionManager.ExtensionManagerService.InstallInternal(InstallableExtensionImpl extension, Boolean perMachine, Boolean isNestedExtension, IDictionary`2 extensionsInstalledSoFar, List`1 extensionsUninstalledSoFar, IInstalledExtensionList modifiedInstalledExtensionsList, AsyncOperation asyncOp, UInt64 totalBytesToWrite, UInt64&amp; totalBytesWritten)
     at Microsoft.VisualStudio.ExtensionManager.ExtensionManagerService.BeginInstall(IInstallableExtension installableExtension, Boolean perMachine, AsyncOperation asyncOp)
     at Microsoft.VisualStudio.ExtensionManager.ExtensionManagerService.InstallWorker(IInstallableExtension extension, Boolean perMachine, AsyncOperation asyncOp)
  </code></pre>
  
  <p>I used to add most of every needed extension and can't understand where does it come from?</p>
  
  <p>Here is extension project file in current state: <a href="https://github.com/Heather/Nemerle/blob/VS2013/snippets/VS2010/Nemerle.VisualStudio/Nemerle.VisualStudio-VS-2013.csproj" rel="noreferrer">https://github.com/Heather/Nemerle/blob/VS2013/snippets/VS2010/Nemerle.VisualStudio/Nemerle.VisualStudio-VS-2013.csproj</a></p>
  
  <p>What should be added to resolve this?</p>