HP iPAQ 914 / 914c Soft reset 

If pressing a button on the device or tapping on the screen does not evolve a response on your HP iPAQ 900 Business Messenger series, reset the device.
NOTE: The device doesn’t have a hard drive that can be formatted. To format the device and restore the factory settings, perform a factory reset.
A hard or a factory reset clears all user-defined settings, programs, and data to restore the device to its default settings. However, the data in the iPAQ File Store folder is untouched. Therefore, before performing a hard or a factory reset, save all your important data in the iPAQ File Store folder.
Performing a soft reset
A soft reset stops all the applications, but does not erase any programs or saved data. It also resets all hardware registers.
Save any data within a application before performing a soft reset.
Follow these steps to perform a soft reset.
  1. Locate the recessed Reset button at the top of the device.
  2. Use the stylus to lightly press the Reset button.
  3. Release the Reset button. The device resets and turns on.
Performing a HP iPAQ 914 hard reset
Follow these steps to perform a hard reset.
  1. Turn off the device.
  2. Press the ok button located on the right side of the device and the Voice Commander button located on the left side of the device.
  3. Use the stylus to lightly press the Reset button, keeping the ok and the Voice Commander buttons pressed.
    Figure 1: Buttons combination for hard reset 
  4. Release the Reset button.
  5. Release the ok button and the Voice Commander button when the Clean Boot message is displayed on the screen. The device restarts and turns on automatically.
Performing a factory reset
Follow these steps to perform a factory reset.
  1. Tap Start > Settings > System > Factory Recovery . The Factory Recovery screen is displayed.
  2. Type 1234 in the text box.
  3. Tap YES . The Clean Boot message is displayed on the screen and the device restarts and turns on automatically.