Time Machine users get "Error occurred creating backup directory"

Some Time Machine users who are using Time Capsule have run into problems in which Time Machine does not create backup directories and exits with an error message.

Apple Discussions poster greeneo:

"I've been using Time Machine with a Time Capsule reliably since March. Now I keep getting failed backup attempts because, "An error occurred while creating the backup directory." Nothing really much has changed except for regular software updates."

These problems are among many small, and in general, easily fixable problems with Time Machine that users have experienced since Leopard was released. Through the various system updates Apple has addressed most of the problems, but they still crop up for some users.

Fixes

Run disk repairs on local volumes The first thing to do when confronted with this problem is to run permissions fix and disk repair routines on all locally mounted volumes with Disk Utility. If there are any problems with the drive structure or file permissions then that could be the cause for the errors, and fixing them should help.

Reselect the Time Machine drive Go to the Time Machine system preferences and click the "Change Disk" button. In the resulting window select "None" as the destination drive and click the "Stop Backing Up" option. This will only stop Time Machine from running, and will not remove any backups already on the destination drive. When the window closes, click the "Change Disk" button again and re-select the backup drive to use. Users may have to use the "Set Up Time Capsule" option for Time Capsule drives.

Delete the TM preferences If the second fix does not work, then completely resetting all of Time Machine's preferences is the next step to try. Locate the Time Machine preferences file, called "com.apple.TimeMachine.plist" located in the /Library/Preferences/ folder (the one at the root of the drive, not in the user folder) and remove it (trash or otherwise move it from the Preferences folder). Then restart the computer and go to the System Preferences to re-setup Time Machine (both the TM drive and the exclude options will have to be set up again).

Reset Time Machine To completely reset Time Machine and start from scratch (the last resort), users will need to reformat the Time Machine drive, and also remove the preferences as described in step #3. After removing the preferences, users with locally mounted Time Machine drives should use Disk Utility to format the drive, and Time Capsule users should use AirPort Utility to reset the device and set it back up again for Time Machine.

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