How to Hard Reset Nokia 5800

Restore the original factory settings

Restore original settings
Select Menu > Settings and Phone > Phone mgmt. > Factory settings.
You can reset some of the settings to their original values. To do this, you need the lock code.
After resetting, the device may take a longer time to power on. Documents and files are unaffected.

Hard Reset with buttons / keys

Press and hold GREEN + RED + CAMERA when powering up, then input default 12345 security code.

Reset the Nokia 5800 XpressMusic device
1. Switch off the device.
2. Remove the battery.
3. After a few seconds, re-insert the battery, and switch on the device.