This is a very basic guide on how to unlock your modem. You will need:
Non Vofafone sim
Generic ZTE dashboard (see optional step)
Install the VF (Vodafone) dongle software as per usual. The drivers need to be installed for the dongle to be read be the computer.
Make sure the VF Dashboard works properly and you can get internet access from the dongle.
Now exit the VF dashboard software and ensure that any other VF Software is killed from task manager and Control Panel > Computer Mangement > Services (Look service starting with Vodafone…), stop and disable.
Make sure that all autoruns on the XP system are turned off as well (http://support.microsoft.com/kb/967715)
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\NoDriveTypeAutorun Value = FF in Hex
Open up Device Manager and have a look at the Ports (Com and LPT). Insert Modem and see what port comes up as the Diagnostics Port when the modem is plugged in.
Take a note of the port and open up hyperterminal, selecting that com port and choose 9600, N, 8, 1 for setup.
Type ATZ and look for an OK
Now type the following commands and lok to see that you get success prompts.
Exit Hyperterminal and unplug the modem / replug the modem. Open up Device Manager and have a look at the Ports (Com and LPT), you should notice that the description wording for the comports is different. In my case before it was Vodafone and now it is ZTE.
Now you should be able to open up DC and unlock that sucker, just make sure that you have a non VF sim card in the modem or your DC program will say it is unlocked already.
Optional and really worth it
Uninstall all the VF crap, Go to http://www.dc-unlocker.com/downloads/ZTE/Dashboards and Download the ZTE Dashboard.
Open up the ISO using winrar or simmilar. Install it on your system and use it with the modem. The Join Air ZTE dashboard has all the drivers.