I've had a similar issue.
If you take either of your computers off the internet, do they still not work?
You can have your "license" removed at Alibre so you can have new license installed. IE, new computer, remove the old computer from licenses list.
I run my alibre on three computers. My desktop, design laptop and some times and additional travel laptop. I'm very thankful that Alibre allows for me to do this. I hate the dongle stuff. I use MecSoft for my CAM and have to carry the dongle with me.
Good luck with your license issue. I'm sure you'll get it fixed. Damn virus.