Forgot an iPhone Passcode? How to reset the iPhone 4 passcode
you will lose all data on your phone
1.disconnect the usb cale from iphone4 and leave the other end connected to your pc
2. launch itunes
3. press and hold the home and power button on the top of the phone to turn off the device
4 while holding connect the cable to phone
5. phone will be detected in recovery mode
you must restart the device
- from itune summery look for restore
- click restore button