I just received a new Lg Optimus phone from the US. Put my AIS 12 call SIM in and though it shows some aspects it doesnt recognize SIM, my number doesn't come up, it shoes working on GSM Thailand lists true and Dtac, but not AIS. I understand there are locks and codes but the phone doesn't say its locked and isnt asking for any codes. Any one have any experience with this? I understand there is alot to this but I have no clue.

Maybe a good idea to take it to a LG store or one of the large electronics plaza's.

It may need some software update but I doubt it to be honest.

Have you gone into the settings and tried to search for the network manually?

Failing that, just buy a sim for one of the networks it does work with. That may be the easiest fix for you.

Had the same problem a few years ago. Some customers left me a Nokia with AT&T stamped on it. Didn't work with 12Call, but fine with a prepaid DTAC sim. Unless you really love AIS, just transfer your number to DTAC or TRUE and use their service.

Where did you buy the phone? (Specifically, the retail outlet.)

Was it sold "unlocked"?

What version of Android do you have?

It seems like that model, LG Optimus T is locked to T-mobile. So you'll need to unlock it, and then perhaps root it.

You'll have to search for, and through, relevant forums and threads like:

http://forum.xda-developers.com/showthread.php?t=1129903&highlight=optimus+T+unlocking

I did a quick search and most posts I found said you had to buy an unlock code, which is generated from IMEI. I see they are generally available on eBay for ~ $3.00. When you have the unlock code, dial 2945#*509#, and enter it.