We recently had a client running Windows Server 2003 R2 upgrade from FileMaker Server Advance (FMSA) 9.3 to FMSA 10. Immediately after the upgrade, we started receiving "Unable to Launch the Application" error messages whenever we attempted to run the FMSA Admin Console.
We attempted to restart the server, but this had no affect on the problem.
Eventually, we figured out that Java had cached some FMSA Admin Console files which were no longer compatible with FMSA 10. In order to solve this problem, we deleted the following directory from our server:
C:\Documents and Settings\USERNAME\Application Data\Sun\Java\Deployment\cache
Once we did this, everything worked perfectly.