Nokia Lumia 820 hard resetWith the phone turned off.
Press and hold the power key until it vibrates.
after press and hold the down key volume till the exclamation mark will be shown on the screen, release the button and input this combination.
Volume Up > Volume Down > Power > Volume Down.
By performing "Factory Reset", all user data will be ERASED. You MUST backup PRIOR to running factory reset & Web update.
If your phone isn't responding
Do the following:
• Switch the phone off, and remove the battery. After about a minute, put the battery back in, and switch the phone on.
• Update your phone software.
• Reset your phone. This restores the factory settings, and erases all your personal content, including apps you've purchased and downloaded. On the start screen, swipe left, and tap Settings > about > reset your phone.
hard reset your Nokia Lumia 820
Factory reset Nokia Lumia 820 from the menuOn the start screen Scroll down to the bottom of the screen. Tap arrow.
- On the Start screen, tap .
- Tap Settings > about phone.
- Tap reset your phone, and then tap yes.