External HD Won't back up

[will0407]

I had a 320GB WD passport drive I replaced the drive with a 500GB WD scorpio blue.

It's been working fine, until today...

I thought I'd ejected it so pulled out the USB. It came up with the error message, so I plugged it back in. It reied to do a time machine back up but keeps getting stuck after about 10GB's of backup.

I've attached an image of the error message I keep getting.

I've tried erasing the drive, erasing then doing a disk repair (which said it needed repairing but was fine after repair)

Not sure what else to try as it still won't back up properly

 

[Sheeds]

if you boot off your install disks and then repair it or erase it again it might work. I had an external drive that had turned into a brick with cables until I formatted it using my install disks, it's working fine now!