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External drive not readable on new iMac

610 Views 7 Replies Latest reply: Nov 19, 2013 10:02 PM by spacbug RSS
Byoung23 Calculating status...
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Jan 23, 2013 3:59 PM

Hi, I recently bought a NEW iMac with USB 3 and Thunderbolt. I am upgrading from an OLDER iMac with firewire 800 and 400. The OLD iMac was operating on OSX 10.58. The NEW iMac is operating on Mountain Lion OSX 10.82. I have been using 4TB G-Drive for about 6 months on the OLD iMac. I connected the G-Drive to the NEW iMac via and I get the message: "the disk you inserted is not readable by this computer."


I go back to my OLD iMac and the drive mounts fine. So I backed up the G-Drive to another external, connected it to my NEW iMac (via USB 3) and re-formatted it. Now it mounts on the desktop and is acting normal on the NEW iMac. However, when I connect it via firewire to the OLD iMac it no longer mounts on that computer and I get the message "the disk you inserted is not readable by this computer."


What is going on?


Whichever computer I format the drive with, it wont mount on the other. I've never encountered something like this! It is important that I am able to use this drive on multiple MAC computers as I am regularly moving between editing systems and collaborating with other people on various Mac computers. I don't think it is a firewire / USB 3 issue as it works with both cabels (once it has been formatted by either the old or new iMac). I am thinking it has something to do with Mountain Lion?


Any ideas and expertese appreciated.

iMac (27-inch, Late 2012), OS X Mountain Lion (10.8.2), G-Drive 4TB External Drive


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