It's probably not a permission problem.Right click on your backup drive on your desktop and click Get Info. Expand the "Sharing and Permissions" section at the bottom. What permissions does it say you have? It should say "You can read and write". If not, you may have to mess with the permissions.
I agree that Time Machine still needs some work on it.Time Machine is really screwy. And its preferences Panel is about the worst one I've ever seen from Apple. It's almost as though they hired a Winblows programmer to write it.
I had a 500 gig drive as my backup and TM worked the first time for about 5 days, then I started getting errors that the volume didn't have enough room on it, even though there was still about 175 gigs left. I reformatted. Still wouldn't work right. Last weekend I picked up a second 500 gig and RAIDed both as a 1 tb volume. TM has been working so far - but I'm only 3 days in. (crossed fingers)
I won't let you eject it as well....no, i don't own any other external drives...
I was going to try just unplugging/plugging in the external hd, but it won't even eject and i'm afraid to yank out the cord when it's not ejected (i can't imagine what app would be using it, i restarted the finder with no luck). oh boy...
You could just turn off your computer...How do I eject it via terminal?
You could just turn off your computer...
Logging out works as well.
To unmount the drive...restart had no effect... meh.