I had the same problem. I had read the same thread and sure enough, GV wasn't my default voicemail. I did *71 and your GV number and it works again. I'm guessing it has something to do with calls being routed through advanced calling instead of regular telephone and the new system needed to be reconfigurated. I don't feel like trying it, but I wonder if disabling Advanced Calling would have restored my call forwarding to GV??? I'm assuming it just two separate systems that are set up differently.