Windows Store App does not pass certification test due to long file path?!

When deploying your app it can happen that you want to publish the update of the app, but certification/publishing fails due the length of the name of some assembly. This happened to as after we implemented support for notification hubs. That means we added assembly Microsoft.WindowsAzure.Messaging.Managed.dll, which has pretty long name. Here is the error which you will see after certification toolkit has checked the application:

FAILED

Performance launch

• Error Found: The performance launch test collected the following results:.

  • The Native Image Generator failed due to long file path for file C:\Tfs\TfsPreview\SecurityNewsApp\SecurityNews.App\bin\Debug\AppX\Microsoft.WindowsAzure.Messaging.Managed.dll

• Impact if not fixed: Application launch time is important for creating a fast and fluid experience for the user. This app will not be accepted by the Windows Store.

• How to fix: You should ensure that your app’s performance is consistent across different machine configurations and does not exceed the minimum requirements or it will potentially fail during Windows store onboarding. The informational metrics can provide insight into areas that could help improve your app’s performance, but do not impact your apps acceptance by the Windows Store. See link below for more information:
  Performance Best Practices
  Known issues in native image generator

To solve the problem, create an empty file nonegen.txt and add it to project as shown below:

This file will prevent the NGEN.EXE to generate the native code during installation of the app. In fact NGEN is the guy who prevents you to have name of the package longer than 88 characters. But please note that excluding of NGEN from build process will slow down startup of the app. In most cases this is not an issue, but sometimes it can be.

More information about this:

http://support.microsoft.com/kb/2716152