Running ATI 11 with Vista Home Premium. (all latest builds) I regularly back up with ATI 11 (from system disk WD500GB to secondary internal WD500GB, or various types of external HDD). The size of the backup TIB files was usually about 85GB, using "normal" compression, with my system drive showing up to 115GB usage. Then I needed to restore off an ATI backup and suddenly the usage on my restored system drive was only about 55GB. I have been assuming this has something to do with the loss of Windows Restore Points (and possible loss of Windows Shadow Images, though Shadow Images not supposed to be available in Vista Home Premium)-- and then as new Windows Restore Points (and possibly Shadow Images) collect the usage of system drive increases very quickly. (after resetting Windows Restore Utility to backup on C: drive - the ATI restoration usually not only wipes Windows restore points but also mucks upo the settings in the Windows utility) Since restoration have done several ATI 11 backups and the size of the VALIDATED TIB files have varied between 43GB and 70GB. Is this normal for the TIB size to almost cut in half after a restoration?