How to unlock Huawei 3G Modem E173, E1550 and E1750

Before starting the unlocking process, there are few things which you should take into account. First, make sure that your data card is detected in your desktop/laptop and you should know your IMEI number(IMEI number is a 15 digit number printed on the device). So now just follow this step by step guide how to unlock your Huawei E173, E1750 or E1550 data card as below :

1. Download  Universal Master Code.exe . Enter your 15 Digit IMEI number as shown in the below screen and press Calculate for Unlock Code and Flash Code.

2. Plug your data card with an unaccepted SIM to your PC.

3. - For E173, It will prompt for an unlock code, just enter the Unlock Code you got from Universal Master Code.exe . ( Your Huawei E173 modem is now unlocked and can be used with any SIM ) 

    - For E1750 and E1550, you have to download    HUAWEI_MODEM_Code_Writer.zip and continue to step 4.

4. Extract the zip file and run HUAWEI_MODEM_Code_Writer.exe

5. Press " Please select Com Port "

6. Press " Detect" and choose your modem type in dropdown list. Then press " Accept"

7. Press " Unlock Modem ", a pop up window will appear asking you to enter the Unlock Code.

8. Enter the Unlock code from Universal Master Code in the field provided and click " OK ".

9. Press " Unlock Modem " ( your Huawei modem E1750 or E1550 is now unlocked and can be used with any SIM)
10. Create new profile for your network provider (using APN and User name and password), try to connect to the internet now.

Note : The above guide cannot be applied with Customized Firmware modem. See also guide to unlock Customized Firmware.