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We currently have a ton of Windows 7 64 machines that have user data that we want to have backups for incase of a failure.

We have a 1 465gb harddrive as the system drive and a 1tb hard drive as a backup drive. We have Windows Backup only backup two folders that the users are saving high priority data to. The problem is that some of these 1tb hardrives are already full because it doesn't seem like Windows Backup deletes the oldest backup set to have room for the daily backup. It just says the disk is full and the backup doesn't run.

Then I noticed that all the folders on the system drive have previous versions. Where are these being stored? What is the difference between previous versions and Windows Backup? Does previous versions only keep the most recent x number and delete the oldest to be able to get the most recent? Can you save the previous version data on a different hard drive to have a fail safe from a system drive failure?


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Previous versions aren't really eating up space. It uses free-space to backup previous versions of the files sure... but if you fill the drive with files... the previous versions get automatically deleted. When performing a backup, the previous versions are not being backed up with the current version.

Previous versions are a feature of the "Volume Shadow Copy" service that implements a copy-on-write architecture for windows, which when a file/directory is changed, a copy of the previous state is stored on the disk for recovery... (if needed) If you fill up the disk... the "archived" versions are auto-magically removed... to make room for REAL files. Unfortunately, you cannot move previous-versions store to another disk. You can, however, enable it or disable it per-volume.

You can disable previous versions entirely... but this will not help your backup situation. At the end of the day... The previous versions are not included in the backup-process. 100gb of data backed up 10 times still takes up 1tb. (ish)

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You should also note that Previous versions will also show files backed by Windows Backup. – surfasb Jan 25 '12 at 21:08

TheCompWiz's answer is absolutely correct, but to add on a little, you can create and use a script to automatically delete older backup files. Of course, you need to ensure you really no longer need those files before doing that.

You can use differential backups to decrease the amount of space recurring backups need. WindowsBackup does this to a degree (see Does built in Windows 7 backup perform differential (incremental) backups? ) but many other backup programs will give you a full differential backup with very granular control over it.

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A script can be a pain to manage but would be the low cost solution here. I'd check out "Crashplan". They have a local client that has some interesting feature sets as well as a cloud component. – Doltknuckle Jan 25 '12 at 22:25

Note that files that were backup with Windows backup will show up under Previous Versions. It is just a quick and convenient UI for restoring files.

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