MM3: Problem updating to new database

[MeMeMe]

I've installed the latest MM3 alpha, but when I try to run it I get the following dialog box:
"There was a problem with updating the database to the newest version."
and MM3 doesn't load.

[onkel_enno]

Try to delete Local Settings\Application Data\MediaMonkey in your Profile (make a backup first) and restart MM3.

[p1ague]

I found this topic by googling that error message, and tried going into that directory (rather than just copying it and deleting it) and renaming MM.DB
The rename failed, it said because it was open in.. I think it said "mediamonkey library," even though it wasn't running. Sure enough, process explorer showed a secret version "running" and terminating that process let mediamonkey start right up. So it may be as simple as it didn't shut down properly the last time you closed it, and the earlier instance is hogging the database.