I bought a Droid 3 (XT862) and unlocked then rooted/flashed it and put my AT&T sim in it. I can make/receive calls and texts, but I can't use 3G. I've tried messing with the APN settings with several different guides with no success. When I click "Operator Selection" I see "AT&T 3G (310-410)" and I have it selected, but still nothing. The 3G icon on the top of my screen has the up and down arrows taking turns flashing white.
And I'm not sure if this option does much, but "Select network" has "GSM Only", "UMTS Only" and "Automatic". Choosing GSM changes the 3G icon to a different style, but I've tried all 3 and nothing worked. And I've seen success stories of other people getting their Droid 3's to work with AT&T 3G so I know it can work, I'm just not sure what I'm doing wrong. Any help would be appreciated, this is my first smart phone and I'm having a rough start with it