I got this error when I had backed up a database but neglected to truncate its log file and shrink the database. Normally you don't notice this because the default in SQL Server is to allow unlimited growth of data files. Here's the error message:
Name: Database log file is full. Back up the transaction log for the database to free up some log space.
Description: Error: 9002, Severity: 17, State: 6
The log file for database 'FOO' is full. Back up the transaction log for the database to free up some log space.
Here's the code to fix it:
BACKUP LOG foo
* The second parameter is the percentage
* of free space you want to leave for
* further growth.
DBCC SHRINKDATABASE (foo, 10)