Time Machine Failed After Upgrade To Yosemite

[Peakoverload]

I have a 3TB USB drive for my Time Machine backup and it's been running fine since I bought it about a year ago. Currently it's used about 1.8TB.

I upgraded to Yosemite on the day it was released and the installation was fine, no problems but ever since I keep getting a message saying that Time Machine has failed due to the drive being Read Only. It tells me to verify the drive and repair it.

When I go to Disc Utilities the repair option is greyed out so I have to verify it first but even after verifying, repair is still greyed out.

Verifying doesn't seem to reveal any errors, it just says:

Verifying file system
Checking Journaled HFS Plus volume
Checking extents overflow file
Checking catalog file
Checking multi-linked files
Checking catalog-hierarchy
Checking extended attributes file
Checking multi-linked directories
Checking Volume bitmap
Checking volume information
The volume Backup appears to be ok
File System Check exit code 0

No matter what I can't get Repair to become active and the drive doesn't appear in Finder either.

I could reformat it I guess but is there a way of getting it working without loosing everything, has anyone else had this problem after upgrading to Yosemite?

 

[Demapples]

My 1 TB Time Capsule failed after the update. Could no longer connect to it. Had it 3 years so got my money out of it. Replaced it with a new external hard drive and did not bother spending a lot of time trying to diagnose it.

 

[MacInWin]

Have you rebooted? Have you tried to use Disk Utility to unmount and then remount the external drive?

 

[bboggess]

I've experienced this before and found that by:

!. Turning Time Machine OFF
2. Un-mounting the drive via disk utility
3. Power down the drive and wait for a minute or so ( in my case it is an external USB drive)
4. Power up the drive
5. The drive should automatically mount and be visible in Disk Utility
6. Repair permissions via the Repair function in Disk Utility.
7. Turn Time Machine ON

These steps usually fix the "Read Only" error that you are seeing. There is the possibility that the drive is failing.

Bill

 

[Peakoverload]

I've experienced this before and found that by:

!. Turning Time Machine OFF
2. Un-mounting the drive via disk utility
3. Power down the drive and wait for a minute or so ( in my case it is an external USB drive)
4. Power up the drive
5. The drive should automatically mount and be visible in Disk Utility
6. Repair permissions via the Repair function in Disk Utility.
7. Turn Time Machine ON

These steps usually fix the "Read Only" error that you are seeing. There is the possibility that the drive is failing.

Bill

That seems to have fixed it! Well it's backed up twice now without problems and the drive now appears in Finder and on my Desktop. I'll keep an eye on it but hopefully it's not failing as thinking about it, I only got it in June.