Lito Yap
Ansys Employee
From your message, "It used to work but all of a sudden it stopped."
Do you mean it worked on a previous version of Lumerical and it is only happening on the latest release 2021 R1? What is the operating system of the Linux machine? Which version of 2021 R1 is having this issue? It seems to be having problem with the Qt libraries on your machine with our 2021 R1.
Best Lito