i have at&t nokia lumia 900, i try to unlock it, but at the end it display "sim card is missing or invalid.", then "no service-emergency call only." the sim card is new with a current phone number. Pls i need help with this phone.::unhappy:
Soooo, did you unlock the phone ?
It'll display a graphic w an unlocked padlock. dial ##7820# to check (works on my Lumia 1520 - ##782# for other devices) ...