I'm having the same issue as this post https://forum.ansys.com/discussion/5669/flexlm-error-15
Installing ANSYS was a nightmare and now that It's been installed has been breaking every other week.
The default port (1055) on the license server is not default and Ansys server keeps opening random ports above 50000. After having this issue multiple times now,
I'm just a student trying to use ANSYS for some research. I do not have access to the server machine, nor do I have the expertise to answer any questions regarding how the server machine is setup. I have created this post to that others can know to have their technical support try looking for undocumented ports via lmutil commands.
If anyone knows why this happening, please take some time to bestow it upon me.