Before you buy a new cell phone or new tablet, please try the following procedure to repair your device. First charge your battery, backup your important data if possible and in most cases take out SIM and SD card before factory reset. It is impossible to recover your data after doing a hard reset, so online backup is always important. For all of your data, a backup should be done on an external device, hard drive, raid system or media. With or without insurance, if your cell phone lost, damaged or stolen at least your invaluable data is backed up in a safe place. If you are about to sell your phone and you want to wipe your personal data, or if your phone affected with virus you have to do a hard reset. In some cases, you can delete the forgotten password or lock pattern from your device as well. All information is for devices with stock based ROMs. If you are using rooted device, always back up your EFS folder first, containing your IMEI info, etc.!
Performing a HTC 8S hard reset 8s WP8 factory reset
Performing a 8s factory reset using phone buttons
Warning! All data will be lost! 1. Turn the power off. 2. Press and hold the VOLUME DOWN button, and then briefly press the POWER button. Release the VOLUME DOWN button when you see an icon on the screen. 3. Then press the following hardware buttons in this sequence: VOLUME UP > VOLUME DOWN > POWER > VOLUME DOWN.
or Reset Windows Phone 8s by HTC
On the Start screen, slide to the left. Tap Settings > about. Tap reset your phone, and then tap yes.
Warning! Always turn off your device before installing/replacing the battery and SIM card.