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TS1550: Mac OS X 10.5: Time Machine stops backing up to external disk

Learn about Mac OS X 10.5: Time Machine stops backing up to external disk

TS1550 What Happens When Disk Utility Cannot Unmount Disk?

645 Views 2 Replies Latest reply: Jan 12, 2013 2:28 PM by Katie \'OConnell RSS
Katie \'OConnell Level 1 Level 1 (15 points)
Currently Being Moderated
Jan 12, 2013 9:26 AM

I am having the problem mentioned in this article but the solution is not working for me since - when I follow all the steps and try to re-partition the external HD - I get the error message:


Partition Failed:


Particition failed with the error: Could not unmount disk.


Trying to reformat a BRAND NEW OWC external HD with 3TB of space, connect via Firewire 800.



Mac Pro Xeon 64-bit Workstation, Mac OS X (10.6.8), 16 GB 1333 MHz DDR3


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