Matlab Licensing error 96-7

Hi,

I've seen a few other licensing error questions but mine seems unresolved after several attempts. I am get a matlab licensing error when I try to start matlab on my local machine. The license is sitting on a license server. There is no problem in using matlab when I try to run it from a computer physically connected to the same LAN network as the server, but I get the license error when I try and run it from a laptop from home, even after I VPN in to the work network. The license file points to the correct server location and port 27000. I can ping the server, but when I try to ping port 27000 specifically using

nmap -p 27000 <license server address>

I get

Starting Nmap 6.40 ( http://nmap.org ) at 2016-08-20 19:22 PDT
Note: Host seems down. If it is really up, but blocking our ping probes, try -Pn
Nmap done: 1 IP address (0 hosts up) scanned in 3.14 seconds

Whereas from a computer connected into the LAN, I am able to ping port 27000. This leads me to believe that I have to allow port 27000 on the server to talk to addresses on all work network computers, including the ones that have VPNed in. Can you advise me on how to fix this?

Thanks!

Siddharth