What should I bring with me besides the computer for in store repair
iMac, Mac OS X (10.7.3)
Some stores ask for photo-ID, some do not. Purchase/registration will be in the Apple servers if it was purchased directly from Apple or registered at some point.
TThanks, however I need to know if I should bring cords, etc
Ok, I interpreted your question to be about documentation. I would take the keyboard and mouse and power cord. They will most likely have plenty of power cords to use, but a keyboard and mouse, especially wireless, may be helpful to have for the service.
Instore repair. What should I bring besides my iMac
