Well, I'll be out of the country for a month or so, and I called AT&T to get the unlock code, which they gave to me after a few minutes of discussion as to why I needed it. However, putting it in yielded no results. I asked earlier (maybe in a different thread) if running an aftermarket ROM would have any effect, and I was told it would not. Was I told something wrong?
Yeah I finally managed to unlock it. I entered the MCC/MNC number for the SIM I am using and it worked. But you need the unlock code to add them. I will post the steps later.
Here are the steps I followed:
1. Turn the phone Wi-Fi OFF and then turn device ON without SIM card.
2. Type *7465625*638*#
3. You will see the NETWORK LOCK screen
4. In MCC/MNC field, enter MCC/MNC code for the provider you want to use. (example: enter 310260 if you want to use this phone for T-mobile USA Sim Card; 310410 or 310380 for AT&T). Check this link for complete MCCMNC for your provider: http://en.wikipedia.org/wiki/Mobile_Network_Code (It is very important to try all the MCC/MNC code if your New Sim Card Network has more than one code)
5. In CONTROL KEY field, enter the Unlock Code
6. Press OK
7. You should get a message: LOCK SUCCESSFUL
8. Turn off your phone, insert your New Network Sim Card and power ON. The phone should be unlocked.
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