If you own an older Huawei modem (like the E220, E1550, or E173u) or a Huawei phone that requires a diagnostic interface, you’ve probably run into the dreaded yellow exclamation mark in Device Manager labeled “Huawei USB COM 1.0” .
Have you solved this issue differently? Let me know in the comments below. This post was last tested with Windows 10 22H2 64-bit and Huawei E173 modem.
This issue typically appears when Windows 10 64-bit fails to automatically assign the correct driver for the device’s diagnostic (serial) port. Without it, flashing firmware, unlocking modems, or using AT commands becomes impossible.
If you’re still stuck, check the exact model number of your Huawei device. Some very old modems (pre-2009) may only work with driver signature enforcement disabled permanently – but in that case, consider whether it’s time to upgrade to a 4G LTE stick.
