> I have what I would think would be a fairly standard setup:
>
> I have Windows Vista machine with an external hard drive that is
> intended exclusively for backup purposes.
> I have set up daily backup of files.
> This has worked well for a couple of months.
> My C: hard drive on the Vista machine has about 200GB of data
> currently. The H: backup drive is 1TB.
>
> Now, the backup drive is full. The daily backups fail with the
> following message
>
> [Window Title]
> Backup Status and Configuration
> [Main Instruction]
> The backup did not complete successfully.
> [Content]
> An error occurred. The following information might help you resolve
> the error:
> There is not enough space to save the backup files. Free up disk space
> or change your backup settings. (0x81000005)
> Backup time: 2008-12-27 19:13
> Backup location: Backup WD (H:)
> [Try again] [Adjust settings] [Close]
>
> To my surprise, it seems that Vista backup does not automatically
> erase the oldest backups when it runs out of space.
> What is the best way of erasing old backups to create space?
>
> I am aware that the daily backups are under a directory named
> H:\ComputerName\Backup Set 2008-08-24 204607\
> with folders named "Backup Files 2008-mm-dd xxxxx".
> I could certainly manually erase the oldest of those folders. But, I
> notice that the oldest of those folders is also the biggest. Which
> makes me suspect that the backups are incremental, and, if I erase the
> oldest then I will no longer have a complete backup, e.g. some files
> that did not change since the first backup, would then lack backup.
> So, again, what is the appropriate way to erase old backups, ideally
> informing the backup system of the necessity to create new backups of
> files no longer backed up?
>
> I have looked at deleting using the advice here
>
http://maximumpcguides.com/windows-vista/remove-old-system-restore-checkpoints-and-complete-pc-backup-images/> but that does not seem to erase any of the daily backups.
>
> "Wbadmin delete systemstatebackup" documented here
>
http://technet.microsoft.com/en-us/library/cc742081.aspx sounded
> promising, but is not supported on Vista.