Linq row not found or changed

Found the solution in: http://social.msdn.microsoft.com/Forums/en-US/linqprojectgeneral/thread/c672c8ee-bf2a-41b4-bb8b-aa76cc5d9b95 (posted by Todd Fleenor)

The problem can be solved this error by redragging the table from the server explorer to the designer and rebuilding. So the designer was out-of-synch with the SQL Table...

Check to make sure your model matches the DB. I've run across this if they are out of sync, in most cases the nullable flag. Check out this article for a possible cause.

I assume you are using the release version of .net 3.5 (Visual Studio 2008).