: Selecting the wrong phone model variant or attempting to downgrade the firmware version below the device's currently installed software version will corrupt its security certificates (Simlock data). This results in a permanent "Contact Retailer" error that cannot be resolved without proprietary high-tier hardware boxes.
Update the firmware to a different region or brand.
While this utility is a powerful piece of mobile history, modern users must exercise extreme caution:
This software is highly legacy. It is designed for older versions of Windows (XP, Vista, 7) and may require specialized drivers or compatibility modes to function on modern operating systems like Windows 10 or 11.