I bought a Samsung Galaxy S2 phone and since I was already using True, I got the True version. I understand they have AIS version as well? Is my phone somehow locked to true? I threw in a DTAC sim and didn't get a signal. Do I need to change the firmware or unlock the phone in order to use other sims? The main reason I ask is True 3G seems to be inactive for the past few days. I have two Android phones and both only seem to pick up GSM. Anyone else have problems with True 3G recently?

I believe that both Truemove and DTAC sell the same version, i9100T. Your phone is not "locked" to Truemove. It should also work with AIS 3G on 900 Mhz although that might require a tweak?

Did you configure the APN for DTAC? Re-boot the phone? Do you have a DTAC 3G plan?

I have True 3G and DTAC 3G at present, no issues as of this morning.

Maybe check...Settings, Wireless and networks, Mobile networks, Network Mode, select GSM/WCDMA (auto mode) or WCDMA only (just to check for 3G, change this back).

I played with the settings a bit and no dice. Because my other phone had the same problem when I switched the sim card, I attributed it to the service, not the phone. I guess I'll pay a visit to Samsung if I can't get it working. Thanks very much for your help.