HT1338: OS X: Updating OS X and Mac App Store appsLearn about OS X: Updating OS X and Mac App Store apps
Currently Being ModeratedMar 7, 2013 11:22 AM (in response to gbread)
try UNplugging the Thunderbolt one, and THEN plug in the one you need. after the files have downloaded, Dissconnect the old one, connect the Thunderbolt one and back up the files. If this does not work i am sorry, but im only at all good at a Mac Mini.
Currently Being ModeratedMar 7, 2013 12:47 PM (in response to gbread)
Maybe this will help. If you monitor the "More Like This" box (top right), other threads appear. Opening them usually displays other threads.
Was the old drive used with a Mac or a PC? If it was a PC, it may be in a format Mac can't read.