In order to hard reset a Nokia C1-00, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
Nokia C1-00 device will be brought back to the default configuration of a brand new device.
1. Press-hold the Power button until the phone turns on.
2. Press Call button to bring out the dialer. Tap the *#7370# code into it.
3. Press Call button again to confirm the hard reset process.
4. Your phone will now reset and restart. Done.