Try to do manual format! just key in *#7370# to your phone u will see this "restore all originalphone settings? phone will restart" click yes then your phone will ask for a code? these are the codes 12345 54321 if still no luck here is the master code 00000(five zeros)
Have u tried updating the firmware? if not go the the nokia official site and download and install nokia software updater on ur pc. the using the dku2 cable connect ur phone to your pc and run the software updater and follow the steps to update the firmware. updating the firmware removes everything on the phone memory.
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