Nokia C7-00 hard reset
Please use this code for hard reset. Do not use the 4 key combo only in case as last resort!You can format your device by typing *#7370# in standby mode. Before the device is reset, you need to provide the lock code. The default lock code is 12345.
Some Nokia phone can be reset via this menu option
Press menu button or enter Menu > Settings > Phone > Phone management > Factory settings > Delete data and restore > YES
Nokia C7-00 hard reset using hardware keys
Be careful!!! It is possible you won't be able to reinstall apps e.g OVI after this methode. Use hard reset code instead.
Turn off yor Nokia C7. Press both Volume down + Camera + Home + POWER ON cell phone.
Formatting the device will permanently erase all user data and settings as well as add-on applications and operator specific settings.