I just got a new iMac, and wanted to transfer all my old Firefox info from my old machine. I downloaded the newest version of Firefox, and it seemed to work fine. Then I tried to move my profiles to the new machine (both on same network). Then I don't know what happened. I had to close Firefox for some reason, and when I tried to reopen it was told by my Mac that "A copy of Firefox is already open. Only one copy of Firefox can be open at a time". I checked in Finder to see if I could force-quit Firefox, but according to Finder firefox was NOT running. I first did a restart of the computer, but when I tried to open Firefox got the same message. Then I threw my Firefox application away and downloaded a new one. No help, same error message. So how do I convince my Mac that Firefox isn't already running? Help, please!!! ''(edited to stop the post from scrolling off to the right)''