try to Hard Reset your device , here the way to do that...
Perform a hard reset with the iPAQ. To perform a hard reset,
1. Press and hold the Answer/Send, Power, and End Call buttons.
2. While holding these buttons, use the stylus to lightly press the Reset button on the bottom (located at lower left base of the iPAQ), of the HP iPAQ until the device restarts.
3. When the HP iPAQ restarts, release all of the buttons, and then remove the stylus from the Reset button. The HP iPAQ restarts and powers on.
CAUTION: A Hard reset clears memory, deletes all data (such as owner information under Setup Wizard and AutoConfigurator) and restores the rw6818/rw6828 to its default factory settings. The action will erase all data that you have created and programs you have installed, but will keep all the preinstalled programs that were in the phone when your phone was first delivered to you. Be sure you have backed up all your data in a mini SD card or on your PC before performing a hard reset