Nokia Lumia 800 hard reset
Turn off your Nokia Lumia 800. Press and hold the following buttons Camera + Volume down + Power until your phone vibrates, then release only the power key and keep pressing the Camera + Volume down for a couple of seconds 4-5s.
or
On the Start screen, tap.
Tap Settings > about phone.
Tap reset your phone, and then tap yes.
Repair Nokia Lumia 800 do one of the following
• Reboot your Nokia 800 phone. Press and hold the power key for about 10 seconds. The
phone switches off. To switch your phone on again, press the power key.
• Update your phone software
• Restore the original factory settings.
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