That doesn't sound like a good situation to be in - being as the Dell hasn't got a CD drive it's not a good idea to uninstall the Vodafone software - it would be a nightmare to get back again.
It might be worth removing the device (internal modem) from the software and getting the software to search for it again.
Open Vodafone Mobile Connect
Click on Manage Devices
Click on the internal modem
Click remove.
Shut the software down.
Restart the netbook
Load the software back up again, and go back into manage devices - if the internal modem is not showing, try selecting Add and see if the software can find it.
If it can't, there is every chance that the internal modem could have developed a fault, in which case Dell should be able to sort it out for you.
Hope this helps
Cartman_81
If I ruled the world....... I'd make make people laugh all day!