I have a 3GS and I was running 3.1.3, and decided to upgrade to iOS4. Upgrade went perfectly, new features are awesome, but now I can't use anything that uses the internet! I can make calls, text, NO visual voicemail, NO Safari, etc.. I have read people resetting their networks (which I've done twice), turning airplane mode on and off (which I've done countless times), and even turning the "Enable 3G" on and off (which.. Well, you get the idea)! I'm at a loss, any help would be greatly appreciated.