Most data cards (probably almost all) are SIM-locked to Internet networks they are assigned, just like mobile phones being locked to a particular mobile network. If you try to insert other (U) SIM card, it will prompt for an unlock code, or warning. Using tools to unlock these data cards are in existence and we will tackle them one by one and steps how to use them.
Huawei Code Tool
This is a small tool used to send unlock code to the modem, in the event no prompt for unlocking is presented. It first scans the COM Ports for the correct interface, and an input box for the unlock code.
Huawei Code Writer
It is basically the same with Huawei Code tool, but much neater and straightforward. Enter the unlock code on the pop-up box.
This is the program to generate the unlock code. Just enter the IMEI of the data card, and copy the key produced.
Universal Master Code
Just the same as the Huawei Unlocker, but with additional feature: the Flashing Code. Flashing code is used for firmware updates, where it asks for the “pass code” to continue updating. This tool also has unlock option for some ZTE, Nokia, VK, LG, NEC models.
Huawei Modem Unlocker (latest)
Get Flash, Unlock codes, automatic unlock, autodetect of Huawei modem, other services like reset modem, restart, enable/disable cd, enable/disable voice, upgrade of download speed upto 7.2 mbps, and upload speed upto 5.2 mbps. Download here