Learn how to use the Mobile Device Unlock code of the Nokia Lumia 635.
SIM unlock phone
- Determine if your device is eligible to be unlocked: Unlock your mobile wireless device.
- Contact Customer Care to request the Mobile Device Unlock code for your phone.
- Turn on the phone with the non-T-Mobile SIM card. The device displays 'Please input unlock code.'
- Enter the unlock code. If successful, the device displays 'Phone is unlocked.'
- Stop if you receive an error message. The device may lock permanently if the incorrect code is entered multiple times.