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Windows 7/2008 command line Backup Size - does it shrink?


I perform a backup of Windows 7 and Windows 2008 using the below command, daily.

wbadmin start backup -allcritical -include:C: -backuptarget\\fileserver\mybackup -user:myuser -password:mypassword

One day I transfered a lot of data to the computer, then the backup occured. The backup stays large even after i removed the temporary data and performed subsequent backups.

Is there a natural checkpoint for the backup to shrink? or is there a command to make it shrink?

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The backup system in windows 7/2008 is a little different to the old NTbackup system. This oe is image based and takes a snapshot on the entire drive with the OS on. I'm guessing thats where the data was stored too?

You may have to try a disk cleanup to see if the temporary files are still hanging around in a tempfolder somewhere.

No, there really isn't a "truncate" feature for the backup command.
So, that means you'll just have to delete (or rename) the old backup so that the next backup run will create a fresh version of the file.


thank you