I had to recently sync my iPhone 3G with my Mac cause my PC was having some issues. It was working just fine, syncing fine and everything. Well I finally got my PC working again and completely restored as a new phone on my PC and now it refuses to back up. It gives me "iTunes cannot back up the iPhone because an unknown error occured (-20)" and can't seem to find anything on the internet with this error. Is anyone else experiencing this at all or is it just me? I'd really like to be able to backup my phone just in case something happens. I'd continue to sync with my Mac Mini but it's an older model(with only 80gb of storage) and all my 200gb of music is stored on my PC so that's not my best option. Any ideas?