Windows Phone links

As of now there is no official solution available in Zune which allows you to backup and restore your Windows Phone ( WP / WP 7.5 Mango )  phone to a state where it was working.  But good thing is because of support from XDA-Forums members,  hx4700 Killer has developed a custom hack which uses the Zune to backup. Disclaimer : I will not take any gurantee if something happens to your phone, It worked for me and should work for every one else but then we have something called as Luck, So use it at your own risk How these tools basically works ? Zune only takes backup when a new update is available.  So in case the update fails, it can use the backup to restore your phone. This custom hack makes Zune think that there is an update available and forces it to take a backup.Same thing happens when it comes to restoring. So everything is getting done by Zune we are just making it think different.

http://www.wpxbox.com/how-to-restore-and-backup-windows-phone-homebrew/