If you need to wipe the T-Mobile Sidekick LX back to factory settings for whatever reason, or if the device isn’t functioning properly, you’ll want to do a factory reset on the device. Please note that this will wipe all data except for anything contained on the sim card, so backup any data you have if possible before performing the hard reset.
1. Go to Menu > Settings > System Info
2. Press Menu, Shift, and X at the same time
3. Select Erase to wipe the flash settings
4. Back at the System Info screen, press Menu, Shift and R at the same time
5. Select Erase to wipe the sign in information
6. Look by the X key (some have said right behind the swivel) and you should see a tiny hole (Not the speaker hole!). Insert a paper clip into the reset hole and press down while holding the Power button.
If your device isn’t working at all to get to the menus, try to do step six alone to see if the device will restart in order to complete all steps.
Alternatively you can try to perform a soft reset first if your device isn’t booting up properly. Remove the battery, put it back in, and then hold the W key down while powering on the device.