sounds like a firewall or antivirus issue! I have never ever seen this problem myself!
Yeah. The central assumption of the question is also incorrect. MC does
not "communicate constantly with a license server".
Lots of programs do, but
not MC. The only time it connects to the license server is when you first register a new installation of MC, and even then, only when you use the restore process inside the application to generate the Install Key (MJR file).
MC can be used on a machine with no Internet connection of any kind. You just have to copy the MJR file (which you created using another copy of MC or by visiting the
license server yourself on a different machine) over to the computer in question and use it to install the license.
So... Something else is going on, cupboy. MC does not do what you think it is doing.
Read this:
http://wiki.jriver.com/index.php/Restoring_a_LicenseIf you're still having trouble, please post details. As TAO1857 suggested, you may have an overactive security application on the computer that is blocking or interfering with MC's attempt to contact the license server. Registry cleaners can also break the licensing if allowed to do their dirty business. Or, you might have broken proxy settings or malware on the system (like a Registry Cleaner, which are basically malware in many instances) that is causing havoc.
In any case, using a MJR file to restore your license will work even if the computer can't get online at all. You should have a bunch of these, as JRiver emails you one each time you try to restore your license (or, you can go to the page linked above and do it yourself).