My phone is frozen - T-Mobile Dash Smartphone

Pop out the battery and sim and wait 10 seconds and put them back in..

here is 2 useful tips:

How to Hard Reset a T-Mobile Dash/ HTCS620:
1. Select Start
2. Select Accessories
3. Clear Storage
4. Type in 1234
5. Select Yes

How to Hard Reset a T-Mobile Dash and HTCS620 without the operating system:
Turn the handheld off, hold the two soft keys (the dashes to the left and right of the phone buttons) hold the power button for 1-2 seconds and then release the soft keys. It should prompt you to clear storage. The “send” button is considered as the green phone button.