How i can do the factory reset on my Nokia Series 40

Select Menu > Settings > Rest. factory sett. (or Reset device or Restore factory sett. or Rest. fact. sett.).

• To reset only preference , but keep all personal data, such as contacts, messages and media file, select Restore settings only (or Restore sett. only or Settings only).

• To reset all preference settings and delete all settings personal data, select Restore all (or All).
• Enter the security code before the restore. If you have never changed your security code, then enter the default code 12345. If your phone still requests a security code or if you have forgotten it, please bring it to the nearest Nokia Care point for inspection.