Whether you want to sell your Lumia 800 / 900 or simply want to start afresh, we show you step-by-step how to hard reset it to factory settings.
There are two ways to reset the Nokia Lumia 800 and 900. The first is to navigate through the menus:
Step 1. Starting from the home screen, swipe left or press the arrow which points right.
Step 2. Scroll down and tap on Settings - it has an icon like a cog.
Step 3. Scroll down and tap 'about'
Step 4. Tap the 'reset your phone' button. If you can't see this button, simply scroll down.
Step 5. A warning will tell you that all your data and apps will be erased, so ensure that you have backed up your phone, or at least your photos and contact details, before tapping the 'yes' button to confirm you want to completely reset your smartphone.
The other way to reset a Lumia 800 or 900 is using its buttons.
Step 1. With the phone switched off, press and hold the volume down, camera and power buttons (the only one not to press is the volume up button which is closest to the top of the handset).
Step 2. Your phone will vibrate. Release the power button (the middle of the three) but continue to hold the other two for five seconds.
Step 3. The smarphone will reset and will be restored to factory settings.