I have the 'preserve last access timestamp' checked, but everytime I do a thorough scan of my computer (scheduled to be done weekly) my system ends up re-backing up everything, as if the files had been altered since the last backup (which is done daily.) I have verified that the timestamp option is checked as my default for on demand scanning, and also verified that the scheduled scan is run with this option. Normally my daily backup only takes 10 minutes or so, as only changed files are backed up; after my weekly system scan the backup can take 4 hours or more. I'm using Vista Ultimate's integrated backup. Is there some other option I need to employ or does the preserve timestamp function just not work with the Vista backup function?