Do it right the first time.
Anonymous posted an answer for this Nintendo DS Lite Console:
"You mean like you bought a used game and don't want to use other peoples data? Somewhere..."
Anonymous posted an answer for this Nintendo DS Lite Console:
"You should have set it yourself when you first played the game. Try just leaving it blank."
Anonymous posted an answer for this Nokia 6230:
"Also when the phone has no service plan you can still call 911"