Error Code: 0x81000031 System & File Backup Problem

Dell XPS Studio8000, Windows 7 Professional, 64 bit

"Your last backup did not complete successfully, your data is not backed up.

Error Code: 0x81000031

Backup error:  Windows Backup failed while determining libraries location of one of the users included in the backup.

Details:  BitLocker Drive Encryption can't be used because critical Bitlocker system files are missing or corrupt. Use Windows Startup repair to restore these files to your computer."


I made an initial attempt to backup my new system, using Windows 7 Home Premium, and received the message that my backup didn't complete successfully.  I continued with my configuration and an upgrade from Home Premium to Win 7 Professional.  When I was satisfied with the configuration I attempted to make another system and file backup and continually receive the above errors whenever I initiate the backup.

I've tried rerouting the backup info to another hard drive without success. My drives are unencrypted and I've never used BitLocker so I can't account for those error messages.  I've looked at the system repair disk options but don't really want to return my system configurations to square 1.  Is there some other way of resetting this error without undoing my configuration?

I hope this is sufficient information.  This is my first attempt with Win 7 so, although, more info may be available I haven't found its hiding place yet.