Try disabling the firewall on both the client system & license server and then test starting NX.
If NX can then work, the solution is to either leave the firewalls disabled or create some firewall rules to allow the license traffic through.
Video linked below explains what needs to be done to fix the the license service for the firewall rules to work.
Are you running NX for the first time? Did it work before?
Did you just install NX for the first time? Is the license server on a different client/server? In that case, do you have network connection?
Ronald van den Broek
Senior Application Engineer
Winterthur Gas & Diesel Ltd
NX9 / TC10.1.2
Building new PLM environment from Scratch using NX12 / TC11