If you are reading this, you are probably staring at your Huawei B311-221 router with a mixture of frustration and hope. You bought it from a carrier like Vodafone, T-Mobile, EE, or Three. It works fine with their SIM card, but the moment you try to use a cheap unlimited data plan from a different provider, you hit a wall.

: Power the router back on and connect a computer or phone to its Wi-Fi. Open a web browser and navigate to the default IP address:

To check the firmware version of your Huawei B311-221, follow these steps:

The B311-221 often runs newer Huawei firmware that cannot be unlocked by simple IMEI calculators. These services use specialized tools (via USB) or server-based codes.