I've been having the same trouble with a client of mine's BUE 11d and this error. I did a help search and it made mention of the location of the catalog files. I checked where mine were going, and they were bing writtne to the C: drive.
I know this server's C: drive is nearly full, 48 Megs free out of 8G. I moved the catalog files to the more available D: drive. Not sure if this will correct the problem, but it might help. You can find the Catalog location under Tools > Options > Settings/Catalog. Good luck.