I have started to receive this message. The backup is being put on a cruzer USB drive connected directly to my computer. There is more than enough room for the backup, 14 gig free on the drive. I was able to backup the file last week. The only changes to quicken have been updating accounts. The Quicken file in question is about 54 meg.
I have another smaller quicken file that I use to track 2 accounts for another family member. I can succesfully backup that file to the same destination so there is not an issue with permissions or connection. The backup drive is the same drive that the Quicken file is on. I then copy the backup directory to 3 other removable drives to have backups in seperate locations.
The file that succesfully backs up has about 20 characters with a hyphen. The file I am having problems with is about 9 characters.
I have Quicken 2011, on Windows Home Vista 64 bit service pack 2.