Use anything else. This tool is not that good and didn't improve much from Vista (read http://www.vistax64.com/tutorials/99709-backup-complete-computer.html and its warnings.)
You can find better.
I have 2 computers (a primary and a secondary computer) both running Win 7 Home Premium. I have used Win 7 "Backup and Restore" to make a "Backup Set" and a "WindowsImageBackup" for the primary computer on a small External HD drive attached to it. However, today I got a large external HD and would like to attach it to the primary computer and give the smaller external HD to the secondary computer, for it to do backups onto (among other things). I have 3 questions. I have full administrator privileges.
1. How do I erase the "WindowsImageBackup" for my primary computer from the small external HD?
2. How do I erase the "Backup set" for my primary computer from the small external HD?
3. Will there be anything special I have to do to make another "WindowsImageBackup" onto the new larger external HD?
Thank you in advance for your help.