Is your iPhone Crashing?
1. Put your iphone in the dock, with the USB cable disconnected from your computer.
2. Make sure the phone is off
3. Once you know the phone is off, press and hold the HOME button then plug in the USB cable to your computer, keep holding the HOME button the whole time.
4. Next it should put It should now show the sync logo on your iphone and it should say “connect to itunes”.
5. Now restore your phone, and you should be solved!
If that doesnt work call our experts at Nexus in Gerrards Cross on 01753 884700
This information was provided by http://forums.macrumors.com