Couldn't connect to display ":0" with Ubuntu / FLAIR

Dear colleague,

I have installed ubuntu on a NICE W10 PC,then installed FLUKA (2011.3.0) and FLAIR(3.0).
Everything was running smoothly until the installation of the cmf patch for February.

Since then, launching Flair, I got the following statement: couldn’t connect to display “:0”.
I tried an “export display” command to fix it but it failed.

Could you please let me know what is needed to recover the possibility to open Flair?

Many thanks in advance for your help

Best regards

Dear Fabrice,

I have some question about your setup:

  1. Did you use WSL to install Ubuntu on Windows 10?
  2. After you start Ubuntu, what is the result of the “echo $DISPLAY” command?


Hi Fabrice,

the February CMF patch (which is a CERN only package) should not have had any impact. It still runs fine on my test setup. Yet, it might be that some link/connection to a local X-server setup was corrupted for whatever reason. WSL by itself does not support graphical output and needs a locally installed X-server.

You can use XWin32, xming or any other. Personally, what I found to work perfectly and with minimal intervention was MobaXTerm, which offers plenty of other useful options.
The following video shows how to set it up: which is very simple.

Hope that helps

Hi Chris,

thanks a lot for providing the solution.
It works perfectly with MobaXterm. it helps a lot.

sorry for the late answer
I did it from outlook, and as you know, it is not transmitted !!