1. dopke's Avatar
    I have been using an unlocked 9900 for about a month now and today it suddenly gave me an "invalid sim card" error and thus cannot connect to AT&T network. Anyone know what's the problem? I've tried resetting and battery pull, but no change...
    01-25-12 03:26 PM
  2. robsteve's Avatar
    May just be a bad sim. Do you have another sim to try in it? Even an old inactive one.
    01-25-12 03:33 PM
  3. kevinnugent's Avatar
    Happened to mine a week ago. Had to have the handset replaced.
    01-25-12 03:37 PM
  4. freethisberrydotcom's Avatar
    Yes it might be the sim card tray. .. Inspect it for some dirt.
    01-25-12 06:59 PM
  5. dopke's Avatar
    I've restarted it and pulled battery a few times now. Now it does come back after the restart and recognize the SIM. But it's already gone back to "invalid SIM card" two more times after the initial... both randomly when it was in my pocket so I don't know exactly when it happened. Is it the SIM or something with the OS? I'll clean out the SIM slot to check for dust...
    01-25-12 09:40 PM
  6. freethisberrydotcom's Avatar
    You will probably have to reload the OS or change the sim.
    01-26-12 10:46 AM