Try a hard reset:-
You can
soft reset your device with the code *#7780# + security code (12345 if you didn't change it) so your device will be back to factory setttings. Your personal data will not be erased.
You can
hard reset your device with the code *#7370# + security code (12345 if you didn't change it) so your device will be as the first day - all data are deleted because the phone is formatted!
If your phone is seriously crashed and won't boot, you can perform the same hard reset this way:
Make sure your battery is fully charged.
Backup your personal data to your computer or an MMC storage card.
Switch-off your Nokia 6680.
Press and hold 3 keys; Green dial key, * Star key, no. 3 key on keypad and then press the power on/off to switch on the Nokia 6680.
Remember, do not let go the 3 press and hold keys until you see the formatting screen.
After a few minutes when the process is over, your Nokia 6680 will be back to the original delivered system.
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EDIT: At your own Risk!
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