If your Stuck in 1x NO 3G/4G Try this...

[vargo]

• Go to the ThunderBolt’s phone dialer. Enter ##778# and hit Send.
• You’ll get a pop-up labeled EPST, with the choice to “View Mode” or “Edit Mode.” You want “Edit Mode.”
• You’ll be asked for a password. It’s 000000.
• Now flip down to “Modem Settings,” and then choose “Rev. A.”
• Change the setting from eHRPD to “Enable,” hit OK, then press the Menu button on the phone and tap “Commit Modifications.”

I do not take credit for this.. I found it on pocket PC .com

[davidetkin511]

thanks! great find, i was going crazy trying to fix that!