Time Machine Not Working

I'm using a standard usb external as a time machine drive and recently unplugged it without ejecting properly, the result of which is that now when I plug in the drive it never gets past the "Calculating Changes..." stage and also will not properly stop the back up e.g. "Stopping Backup..." never stops, would anyone have any idea how to scrap the whole thing and start off from scratch ? I Don't mind losing the past recoveries so long as it actually works

Thanks in advance

If there is nothing else on the drive that you want formatting the drive and going back through the setup procedure to designate it a Time Machine drive should work. Before you do that though have you tried checking the drive for errors using Disk Utility? Unplugging without ejecting can cause directory damage and resulting unusual behavior but Disk Utility can sometimes repair it without reformatting.