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lukeyroo Author

Level 1

4 points

Time Machine Backup is slow (perhaps corrupt?) after Mountain Lion upgrade

Hello!

I managed to download and upgrade from Lion to Mountain Lion yesterday. Before the upgrade, I performed a backup via TM just in case. Now, in Mountain Lion, the backup prepares and begins around 12GB of backups but never gets passed 2MB of data transferred. The TM logo keeps turning, the external HDD is clicking and the activity light is blinking to indicate communication.

I vaguely remember having a slow backup after upgrading from Snow Leopard to Lion, but never *this* slow.

Has anyone else encountered a similar issue or know of any diags I could do? As a prerequisite to this, I have attempted to verify the disk in Disk Utility but it seemed to be taking a long time (around 2 hours without completion) to verify, too.

Thanks =]

MacBook, OS X Mountain Lion

Posted on Jul 27, 2012 5:56 AM

16 replies

mleffler

Level 1

0 points

Aug 6, 2012 6:46 AM in response to John Scott1

I had similiar issues. I had to reformat my TM drive and now backups are fast and reliable again. However, I had to move all my old backups (which I didnt want to lose) onto another drive first, which took about 18 hours.

Time Machine Backup is slow (perhaps corrupt?) after Mountain Lion upgrade

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