You'll have to do a hard reset of your phone. Here's how to do it:
- With the device powered off, press and hold the 2 soft keys.
- Whilst holding the 2 soft keys, press the Power Button once.
- If successful, you will receive a screen asking you confirm the reset.
Note: it can take a few seconds for the message to appear and you should continue holding the 2 soft keys until it does.Follow the onscreen prompts.
You are going to lose all the pictures, ringtones, videos, music, and such; but this is the only way to use your phone again. Good luck!
Sources
- http://www.phonescoop.com/phones/p_forum.php?fm=m&ff=1041&fi=1158993
- http://community.htc.com/na/htc-forums/windows-phone/f/85/p/404/726.aspx