PUK code unlock: Microsoft Lumia 640

Learn how to PUK unlock the Microsoft Lumia 640. If you enter a PIN code incorrectly several times in a row, the device blocks you from attempting again and may also permanently damage your SIM card.




Identifying PUK code error messages

Confirm that you are receiving one of the following or similar error messages on your device.

  • "PIN code blocked. Enter PUK code."
  • "Enter PUK code."
  • "SIM card locked. Emergency calls only. Please contact Customer Care."


Entering PUK codes


Important: You must call Customer Care for the PUK code. Entering the wrong code can permanently damage your SIM card.


  1. Contact Customer Care to request your PUK code.
  2. Enter the PUK code.
  3. Tap enter.
  4. Enter a PIN code of your choice.
  5. Tap enter.
  6. When you see the message "confirm new SIM PIN," re-enter the PIN code.
  7. Tap enter.