Question : Problem: Differential backup size very large

Hi,
I have a Windows 2K3 Domain controller with roughly 320Gigs of data including user areas. I have implemented a backup procedure wherby every Friday a full backup is taken. I then have differential backups running for Mon, Tues, Wed and Thurs.

This process seems to work fine, however the differential backup size is 100Gigs, between the full backup on a Friday and the diff backup on the Monday. I have checked the individual backup jobs and know that folders are being backed up backed up during the diff should not have changed as they are in areas only I have access to.

I am guessing that the DC is running some kind of scan or defrag automatically although nothing is set in  scheduled tasks. The only thing that runs daily is the sophos virus scan, but if this was causing the problem I would expect all of the files to be backed up as the scan is performed on the entire disk.

Does anyone know what may be causing this?

Thanks in advance.

Andy

Answer : Problem: Differential backup size very large

ok then it's definetily the virus scanning process causing file changes somehow. leave the backupset configuration on change journal, as it is the fastest method.