Do not use ThumbnailURL when registering a Windows Vista Media Center application

I recently received a question from a friend of mine who is developing a Windows Vista Media Center application.  He was registering the application so that it would appear in the Start menu, but was running into a problem getting the application tile's thumbnail image to display correctly.  Instead of displaying the image that he specified in his registration XML file, it displayed a blank blue square.

After reviewing the documentation included in the Windows Media Center SDK for Windows Vista and experimenting with a couple of scenarios, he found that this issue was caused by using the deprecated thumbnailUrl attribute instead of the imageUrl attribute in the entry point in his registration XML file.

Unfortunately, he was using the Windows games that are included in Windows Vista Media Center as an example when creating his registration XML file.  These games all use the thumbnailUrl attribute instead of the imageUrl, as you can see if you look at an example of the chess game in the following location in the registry on a Windows Vista Home Premium or Ultimate system:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Media Center\Extensibility\Entry Points\{115EADF1-41C4-471b-8FE5-7A52B91BFE75}]
ThumbnailUrl=%ProgramFiles%\Microsoft Games\Chess\ChessMCE.png

Because of this use of the ThumbnailUrl value, you will see a blank application tile in the Start menu for these games by doing the following:

  • Launch Windows Vista Media Center
  • In the Online Media strip, select Program Library
  • Right-click on one of the games and select Add to Start Menu
  • Click Yes to confirm that you want to add it to the start menu
  • Return to the Media Center start menu and look at the tile created for the game

For more information about options for configuring images for custom start menu tiles in Windows Vista Media Center, please refer to this blog post as well as the Windows Media Center SDK documentation.