What is wrong with my Time Machine backup drive?

[jrm27]

Hi all,

I've been using Time Machine with an external 2TB drive for a while now (at least a year), without any problems. The other day when I came in, I had a notice on my screen that TM couldn't back up and that there was a problem with the drive.

It appears that I no longer have write-access to the drive. When I go into the info, I don't even see my profile in the "sharing and permissions". Which seems odd. I get this message when my comp tries to read the drive:

You can still open or copy files on the disk, but you can’t save changes to files on the disk. Back up the disk and reformat it as soon as you can.

When I try and copy the backup file to another drive, so I can reformat my current TM drive, I get this message:

The backup can’t be copied because the backup volume doesn’t have ownership enabled.

Any thoughts on how I can fix this? I'd like to reformat the drive, but I don't want to lose the data backed up. Any thoughts? Thanks!