A hard reset will reset your N73 phone to the point it was when you got it. I keyed in *#7370# and it prompted me “restore factory settings to default?” I clicked yes. It then asked me for my “lock code”… I keyed in 12345 and clicked OK. The phone restarted and asked me to select my current city, current time, and current date. It then asked me if I wanted to do the tutorial which I skipped. Everything seemed to work okay. Prior to doing this hard reset I had upgraded my N73 firmware during March 2010.