For newer modems, the "Huawei Modem Unlocker v 5.8.1" will detect the device but generate an "Invalid Code" error every time because Huawei changed the checksum algorithm in 2019.

: Connect your modem to the computer via USB and launch the software. Detection : Click Refresh or Detect to find your device. Unlocking : Select Auto-Unlock Modem and click Unlock .