Note: before proceeding with steps below, insert operators sim card that does not work with device. For example if it's locked to operator "A" insert operator's "B" sim

Launch DC-Unlocker client software

Select manufacturer: ZTE modems, model leave Auto detect (recommended).

Press "Detect" button (Big magnifying glass)

Wait till DC-Unlocker fully detects device

Open Server tab, enter your username and password that you received after credits purchase. Click "Check login". (you can buy credits here www.dc-unlocker.com/buy).

If DC-Unlocker/Vygis/Rocker/Infinity dongle is connected, do not enter username and password, only click "Check login"

Open Unlocking tab, click “Unlock”

Wait till you see a message that modem is unlocked

After you see that modem successfully unlocked, restart it by disconnecting and connecting back. Now you can use it with any SIM card.