Well the procedure of formatting your Nokia phone is pretty easy. Here is Guide on How to Format Nokia N72, N73, N81, N95, NSeries Phones.
How to Format Nokia N72, N73, N81, N95, NSeries Mobile Phones.
editTips
When you should format your Nokia Symbian Series 60 phone? If your phone has slowed terribly and you keep
getting system error messages.
Do it by yourself and save your money. You don’t need to send your phone to get repaired somewhere
and being charged for the cost.
Some licences are in the memory card. See it before formatting.
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Warnings
Make sure you're not using memory card password protection, because you can lose access to data
stored on memory card after formatting.
Method 1: Three Finger Reset for Nokia Phone
1. Switch off your Nokia phone.
2. Hold down the following three keys, Green (call answer button) * Key, and Number ‘3? key.
3. While holding these buttons, press the power button and switch on the phone.
4. Wait for message ‘Formatting’ to appear on the screen and release all keys once you see that message.
Method 2: Hard Format of Nokia Mobile Phone
1. Switch off your Nokia phone
2. Now Press following key sequence *#7370#
3. Enter Default lock code is 12345.
4. While holding these buttons, press the power button and switch on the phone.
5. Wait for message ‘Formatting’ to appear on the screen and release all keys once you see that message.
Method 3: Soft Reset of Nokia Mobile Phone
1. Switch off your Nokia phone
2. Now Press following key sequence *#7780#
3. Enter Default lock code is 12345.
4. While holding these buttons, press the power button and switch on the phone.
5. Wait for message ‘Formatting’ to appear on the screen and release all keys once you see that message.
Please Note: The Above Nokia Phone Formatting method will erase all your Phone data. So do backup before proceeding for Formatting