Is my WD External Drive Dying?

[Badradio]

About 4 months ago my Time Machine told me it couldn't write to the drive (WD MyBook Pro) anymore, nor repair it, but it could read it. I formatted the drive, did a full backup with no problems, but once the backup was complete, the next time it tried to access it it came back with the same error: can't write, can read fine. Last night I was trying to fix it again and it wouldn't even start up.

I bought a new external disk at lunch, but before I set it up, I wanted to try the old one one last time, and it's happily creating the initial backup after I formatted it (MacOS Extended). I'm pretty sure I'm going to have the same problem though - it'll write the initial backup, then switch to read only. Has anyone experienced this, and is it fixable, or is this just erratic behaviour indicating that the drive is on its way out?

Thanks,
Steve

 

[Badradio]

Ok, this is really strange.

The initial backup got half way through, then threw an error saying it couldn't complete the write. I checked the permissions for the drive and it's set to read only for everyone. I logged in as root and tried to reset the permissions on the drive. It has two partitions - "Time Machine" and "External". I can reset the permissions on External and create folders on the drive, but "Time Machine" is locked to read only and I can't change it, even as the root user. This has to be a software issue, right?