Lito Yap
Ansys Employee

@George Kountouris,

From the screenshot your computer is unable to communicate with the server on TCP ports 1055/1056. 

Ensure that the license server has been configured with static ports and these ports are allowed access on the license server.
>>> Ansys license manager configuration and license file installation – Ansys Optics 

You mentioned that other users on your network can access and checkout the license from the same server. Are these users/computers connected to the same local network as the server (same building/room)? 

Other people are using the same licensing method and it works fine.  The machine has a working internet connection, and is running Ubuntu 20.04 LTS.  The server used can ping my network ip just fine, and I can do the same, so it seems that the server should be reachable.

Is your computer connected to the same local network as the server? Or are you trying to connect from home? If you are not on the same local network (LAN), consult with your IT on how to connect to the server from home via the Internet.