So last night I upgraded my iPhone 3GS to OS4... And after the entire process I would have full 5 Bars and 3G signal but would not be able to use any data at all... and when I made calls it would say "Call Forwarding Activated", when I received them it would say "Incoming Call Forwarded"... No go after many different reboots, syncs, etc. I called Apple iPhone support. Gentleman spent an hour with me, we tried many different things, and no avail. He would up having to call me back like 5 times, and would up getting AT&T rep on the phone. She spent 30 mins with me and left me with "You're going to need to restore. I'll call you tomorrow to check on you." So when I restore completely, I get the 5 bars and service and the phone works. BUT AS SOON as I sync my phone and get my contacts/apps/music/etc. and the phone ends the sync, same thing: Data doesn't work *AT ALL* but it looks like its working and the phone "call forwards." I have redone this 5 times since 9:45 last nite. I am at the point now where I've restored and my phone seems be working but I have not synced it so I have no contacts/apps/music/etc. --- it's like its NOT MY PHONE, because as soon as I do I will lose my ability to actually use the phone. Does anyone have ANY Help, please? Thanks in advance, I am clueless.