4 Nokia

Tip 2 : Shit happens, on a smartphone, its inevitable u do something wrong, and tis calls for a format of fone. to format the fone, press *#7370#, then enter the lock code, which is the sec code of the fone. NOTE: batt must b full, else if format is disrupted by low batt, consequences will b disatrous
I heard the code *#7780# works too, pretty much the same i tink.
for 6600 users, to format the fone, theres an alternative way. Press and hold <3>, <*>, and the buttons, then power on fone, keep holding on the 3 buttons, till u come to a format screen. tis method ONLY works on 6600, and need not enter the sec code. BUT sec code wun be reset to default 12345.