Perform a soft, factory, and alternate master reset of the device.
INSTRUCTIONS & INFO
A master reset reverts the device back to factory settings. It will permanently erase all personal data, preferences, settings and content such as pictures, ringtones and apps that are saved to the device. Data stored to an SD card will not be erased unless otherwise selected. It is recommended that you save (backup) important data before proceeding.
To begin, tap the Start icon or Windows button.
Tap Settings.
Tap Update & security.
Tap Recovery.
Under 'Reset this PC' tap Get started.
Tap Remove everything.
Select Desired reset. Note: You must have the device plugged into a power source as this process can take up to a few hours.