Peter Serano
Ansys Employee

There are a few things that could blocking access to the license server:

1) Windows Firewall: You can temporarily disable the Windows Firewall to see if it's the issue. If it works when the firewall is disabled you'll need to 'allow' the ANSYS programs to access the internet - or manually open ports 110, 1055, and 2325 on your local machine.

2) Anti-Virus / Anti Malware: Additional security software can also block the ports the license server communicates on - like the firewall, you can temporarily disable it to see if it fixes the problem - if if does, make sure the ANSYS programs are listed as allowable exceptions. 

3) Host name resolution: If your license server is specified as a host name, try re-running the installation and use the direct IP address to specify the license server PC instead of the host name

4) Issues 1 & 2 can also effect the license server so repeat those steps on that PC as well to make sure the proper ports are open and accessible on your LAN.