Use any GSM SIM card from any provider worldwide.
Before attempting to flash or unlock your E173u-1, ensure you have the following: Huawei E173u-1 Unlock Firmware
Do not unplug the modem or turn off your PC during this process, as it can "brick" the device. Step 4: Installing a Generic Dashboard Use any GSM SIM card from any provider worldwide
You only have 10 attempts to enter an unlock code. If you exhaust these, you will need a "Counter Reset" tool or a deep firmware flash. Huawei E173u-1 Unlock Firmware