I bought the iPhone 4S used and it was jailbroken. Without knowing of the aftermath, I restored the phone on iTunes. Now the phone showes the USB pointing at the iTunes logo. In addition, the phone is not detected by iTunes. I am looking on lone and I am yet to find anything.
try put your phone into DFU mode (if you don't know what that is, I'm sure Google will be a better friend on this) and if your computer still doesn't detect your phone, try reinstalling iTunes. Good luck, mate!
I had the same problem with itunes telling me I wasn't connected to the internet even though I was. I kept trying for several hours but always got the same warning. So then I disconnected the phone and uninstalled itunes. Then I powered off my computer and unplugged everything including the wireless router. I waited 15- 20 minutes, plugged everything back in and restarted. I re-installed itunes and then waited a full 2 hours before connecting the phone to itunes. It completely restored and I got no error messages.