Can't backup iPhone, says that my current backup is corrupt

I am trying to back up my iPhone but when I connect to iTunes and try to back it up I get the following error: 'iTunes could not back up the iPhone "my phone name? because the backup was corrupt or not compatible with the iPhone. Delete the backup for this iPhone, then try again.'

I don't have a backup for this phone anywhere. I checked in the hidden directory that iTunes keeps the backups in and there aren't any bacups in there at all. I don't have any backups on iCloud either. There aren't any 3rd party utilities on the phone either.

I've read many of the tech bulletins on this type of problem and none of them have been able to address the issue. Because of this I can't upgrade the OS, sync files/music, or (of course) back up my phone.

Anyone have any suggestions?