Originally Posted by
Xero I've tried deleting and re-installing itunes but nothing happen...
It's not iTunes that you need to uninstall/reinstall. It's the Windows drivers for the iPhone, as
whmurray mentioned above.
Connect the iPhone to your computer and open Device Manger. Find the iPhone in the list (it MAY be listed as a generic looking Apple device). Right click it and select Uninstall. When complete, disconnect the iPhone, wait a few seconds and reconnect it. Windows should detect the device and reinstall the drivers. When complete, open iTunes.