I have no idea why your firewall would block it. If you are just using the builtin windows firewall, then this most likely isn't a firewall issue. That firewall doesn't block outgoing things as far as I can tell.
If you have a firewall other than the one built into Windows, make sure its set to allow VRS.
If you are just using the Windows firewall, go to the control pannel. In classic view, just go to "Windows Firewall." In the Catagory view, go to "Network and Internet Connections," then "Windows Firewall." Next go to the exceptions tab and make sure VRS is checked. If its not there, try manually adding.
Other than that, the only other things I can think of currently to suggest are; make sure you're running the newest version.
Can be obtained here. Also, if you changed versions you might need to do
this.
If that doesn't solve your problem, well, I think I might be out of suggestions.