My HTC Titan says SIM Error every time I try to unlock it with the unlock code and T-Mobile SIM inserted. I haven't been able to find an explanation.
This is my problem, but with the Red NOKIA LUMIA 920. I tried putting in many different T-Mobile SIM cards, and the phone simply won't ask me for the unlock code. (Yes, I do have the unlock code -- AT&T supplied it to me. But there is no way to enter it.) The phone boots up with a T-Mobile SIM and shows, for a moment, the Airplane Mode icon, then up comes an icon of a SIM card with a Circle with Diagonal Bar symbol over it.
Nope, I don't have the original ATT SIM card to insert (bought this phone on Craigslist), but the Lumia 920 seems to resist taking the ##782# command anyway, saying that command is not in its library. Yep, I've factory-reset the phone, and the first time I did that, it locked up in the famous gear-lock position. I was able to rescue from that, and re-factory-reset, twice since, each time to completion. And, no, that's not the problem here, because the problem existed before AND after.
The phone does recognize the T-Mobile SIM and in Settings>About it shows the SIM number AND the T-Mobile phone number -- almost as if it were already unlocked. But the phone says No Service
instead of T-Mobile
and won't operate. It will check for updated software and do a number of things when WiFi is on. But it won't ask for the unlock code.
I know I am not the only person to experience this -- and I have checked all aspects at both T-Mobile and ATT: No, my IMEI number is not blacklisted with either carrier. Both carriers show clean IMEI.
There was one time where, briefly, after boot-up, and after the Airplane Mode ICON disappeared, I saw T-Mobile appear on the phone tile for a few seconds before the phone went to No Service. So it's almost as if the phone is already unlocked, and checks-in using my T-Mobile active SIM, and then gets an instruction from somewhere to show No Service. Odd.
If you've seen this with a Nokia Lumia 920, please post so it can be solved.
I have started a separate thread for this problem here: http://forums.windowscentral.com/no...-enter-my-valid-att-supplied-unlock-code.html