I am using Windows 7 backup to backup daily with a data set of about 600Gb to a 2Tb external drive. With incremental backups this should run for ages before any disk space management is required, but it is doing a full backup every 3 days, so it only goes for just over a week before the drive is full. What determines the frequency of full to incremental backups and is this ratio variable, perhaps in a registry key?

Hi, Did you set backup on a schedule? When you first set backup option, it will ask you how often do you want to back up, you can remove the option “Run backup on a schedule”. If you have set before, you can also turn off schedule on the left pane from control\backup and restore. Regards, Leo Huang Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

As I said in my original post, I have set backup on a schedule to run daily. My question relates to the ratio of full to incremental backups, not scheduling. In an incremental backup regime, I would expect a full backup to run about once a month, not every 3 days.

Hi, If you want to select a different time for backups or change what and where is being backed up, click Change settings in Backup and Restore window. See this picture: https://skydrive.live.com/?sc=photos#!/?cid=77945bfb2257be5e&sc=photos!cid=77945BFB2257BE5E&id=77945BFB2257BE5E%21223 Regards, Leo HuangPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

I don't know how to make my question any more clear, but you are not answering any part of it. I do not want to select a different time. I do not want to make any changes to what and where is being backed up. I want to decrease the ratio of FULL to INCREMENTAL backups. It is ridiculous for a backup solution to do a full backup every 3 backups.

Hi, Sorry for my misunderstanding. The backup Windows 7 follows is incremental backup. Windows Backup will add new or changed information to your subsequent backups. If you're saving your backups on a hard drive or network location, Windows Backup will create a new, full backup for you automatically when needed. Windows7 backup provides an incremental backup functionality. And the incremental would be based only upon the most recently taken backup. However in your case, if you swap the backup target after every full, the next backup would be full every time. And the issue may be caused by "Windows Media Player Network Sharing Service" updating the ChangeTime of all files under c:\Users\Public folder every time machine is rebooted or resumed from sleep. Disabling this service helped avoid future incremental becoming huge. Hope that helps. Regards, Leo Huang Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Thanks very much, we're on the right track now. It isn't just backing up a lot of files, it creates a completely new backup set every after every 3 daily backups. The backup target is never changed: Day 1: New full backup set, all files Day 2: Incremental backup to the same backup set Day 3: Incremental backup to the same backup set Day 4: New full backup set, all files Day 5: Incremental backup to the same backup set Day 6: Incremental backup to the same backup set Day 7: Attempts to create yet another new full backup set and runs out of disk space You can see the individual backup sets by going into Manage Disk Space.

NickC4555 - I fear you will remain frustrated. MS staff seem to have no idea themselves what determines the start of a new full set. If they had experience of the real world, they would know this should be under user control - even if the user in question is a dummy. I have wasted best part of a day trying to understand the backup & restore from the useless documentation provided. The algorithm controlling starting new full sets, whatever it is, is useless for most of us who have 100's on GB of photo and music files. For these especially we need to contol the full sets, as backup disk drives soon fill up. W7 is useless in practice for this. The second ludicrous aspect is that I have found after upgrading by trial and error that system images will also image your second original and much larger original XP partition as part of the same system image - whether you want it to or not! The system image is therefore gigantic. And fatally the documentation does not indicate whether or how you restore images to a different sized replacement hard disk. Overall this is not quite fit for purpose. It looks designed by the most junior programmer with no worldly experience. Do MS wan to win? Consequence is I will myself 1) maintain by own previous system imagiung program for system image backups 2) continue to use MS SyncToy (or similar SyncBack) to regularly backup my huge music and photo archives. 3) use W7 backup and restore at most only for document files (it seems to backup any outlook.pst files etc hidden in ProgramData), although the documentation is dire, and the lack of control over new full sets (or explanation of how it decides to "start" a new one) is laughably unprofessional. Even a rank hobbiest need more than this. My 45 years IT experience did not help me come to terms with my disappointment at this feeble attempt, but maybe by now I'm worldly wise enough not to be surprised.