Encoding video files for the web to be displayed in Microsoft’s great new Silverlight runtime is pure fun with Microsoft Expression Media Encoder.

However, while I was in the middle of developing a Silverlight prototype for one of my clients, I encountered that my version of EME no longer delivered Silverlight detection JavaScript, that worked with the RC 1.0 version of Silverlight.

I asked Scott Hanselman and Tim Heuer who have both digged into Silverlight detection scripts before and both pointed me to the EME Preview Update. With this update installed EME should provide a new set of Output templates labeled “RC” which target the RC 1.0 version. Unfortunately, even after uninstalling and reinstalling the full Expression app stack, the templates did not show up.

Finally I found the “bug”: I have a long term habit to install the OS on drive C: and all apps on drive D:. So I did install EME in “d:\program files\...”. The Preview Update installer, however, does not allow you to change the installation directory nor does it check where EME has been installed. Thus the updated templates delivered by the update installer were saved anywhere to drive C: where EME installed on drive D: could not find them.

Reinstalling EME to “c:\program files\...” solved the problem!