How to deal with X2Go Client error “Unable to create SSH tunnel for X2Go session (NX) startup”

Today I had a weird problem – my X2Go Client just kept saying “Unable to create SSH tunnel for X2Go session (NX) startup”. I tried to reboot remote server but no luck. What is the solution?

It’s rather easy – reboot the local computer you are trying to connect from (yes the PC you are sitting in front of), after that it should be fine.

Setup: Ubuntu x64 server 14.04.3 LTS running XFCE as GUI. The client I was connecting from: Windows 7 Pro x64.