Hi levig and welcome to the eForum
I'm sorry to hear that you are having problems with this and can completely appreciate how frustrating this must be for you, especially as you don't have an ADSL connection to use as a back up.
My first suggestion is always to pop it into a different USB port and give it a few minutes. That usually then forces things through and the computer picks the device up.
Failing that, the other thing you can try is to download and install the latest version of the VMC software, which can be found here -
Vodafone Mobile Connect Software - ( I understand you do not have a connection at the moment , so to get this installed it will need to be download elsewhere and then transferred to your PC)
Please give this a go and if you have any more questions just give me a shout and we'll be happy to help
Thanks
Wayne
eForum Team