Backup Period Too Long

I have 300GB of my hard drive partitioned off for backups, and I periodically do a backup on an external hard drive. I haven't had a problem with this setup until a few days ago, when my backup space completely filled. This wasn't typically a problem; I'd just delete some old backup periods and move on. Now, however, I discovered that my backup period is 3/27/11 through today, and I can't delete that or I lose my entire backup. (Before anyone asks, I do save only the most recent system image.)

Is there any way to manually control the backup period time to prevent this from happening in the future? I'll solve my immediate problem by extending my backup partition until I can delete an old backup period, but I'd like to prevent this from happening.

Thanks!

My experience has been that Windows (file/folder) backup will continue to add to the existing backup set until at some point it decides to create an additional new backup set.
- A reimage will trigger a new backup set.
- Change of backup location will trigger a new backup set
- deleting all existing backups will trigger a new backup set
Apart from these observations I don't know what algorithm Windows uses to trigger new backup sets.

It's clumsy, but you can use "Change settings" to toggle between two backup partition locations to achieve what I think you want.

Windows backup (excluding images!) adds incrementally to the set. If your sets are getting too large then you probably need to prune off some of the more static data using simple drag and drop to a location and exclude this from the normal backup set.

I think the mechanism is mentioned here:

https://www.sevenforums.com/backup-re...-registry.html

Sorry, by backup period time, I thought he was referring to the time period before an automatic full backup will take place.

The incremental backup shortcut is very helpful. I don't know much about changing the backup location, but I'd prefer using an external HD for backups rather than a partition in the PC, and making sure that the disk space is more than enough.

Finally, FWIW, I stopped using Win 7 backup except to make an image of the PC monthly, and am using Genie Timeline Free for incremental backups. That way, I have a set-and-forget system.