I changed the computer name of my iMac in System Preferences and then logged out, when I logged back in all my files were gone. They're still on the computer, but I can't open any of them. I opened iTunes and all my music was gone, opened iPhoto and all my photos were gone, the files are still on the computer but I can't open them. So I tried changing back the name to what it originally was and still the same outcome. Someone please help so I can get all my files back!