Msg 21, Level 21, State 1, Line 1 Warning: Fatal error 9001
That error means that the log for your database (or for tempdb) is not avaialble for some reason.  That's a serious problem that is usually fixed by restarting the server.

If the problem recurs, it could be many things having to do with problems with your storage system.  One possible thing to check is to see if your database's log file (or tempdb's log file) is running out of space (not sure if that can cause this error or not).