I lent my laptop to someone and when I received it back the only account I could get into is guest. I am using windows 7 starter. Everything I try to do to try and fix I need to ok through a uac account.

Give a try to various programs http://pcsupport.about.com/od/toolsofthetrade/tp/passrecovery.htm http://www.resetwindowspassword.com/recover-windows-7-password.html If you do not manage to recover password, then remove hdd from computer and backup data in anothe computer, and reinstall Windows 7. OR If you have backup copy, restore the latest backup copy. Regards Milos