Connect your iPhone to your MAC or PC using the USB cable then follow the instructions below
- Hold down both the home and power(wake/sleep) button
- Release the power button after 10sec (exactly 10sec) but continue holding home button
- Wait for iTunes to detect your iPhone (windows will notify you that a new hardware installed and ready to use…)
2nd method (works with firmware 1.1.4 or lower. if your iPhone running on firmware 2.x use the 1st method)
- Download and start ZiPhone
- In advanced features click DFU mode
Note: After entering into the DFU Mode your iPhone screen must be black, if iTunes logo appears on it your iPhone now in Restore Mode not DFU !
Difference between DFU Mode and Restore Mode
DFU mode doesn’t boot up the MAC OS on iPhone – therefore it doesn’t communicate with iTunes “as much” as in Restore mode and iTunes can’t decide to interrupt downgrading the firmware etc.