I just had the problem that I couldn't start my favorite IDE IntelliJ IDEA. It didn’t discover the company license server because it has to be accessed via a proxy. Somehow, the proxy config went missing. Hence, I only got the “Cannot obtain ticket from …” dialog. I couldn't access the proxy settings because I couldn't get past this dialog and start IDEA.
Here’s how you setup the proxy before starting IntelliJ IDEA.