As detailed in KB0015722 the current (as of July 2021) versions of X2go on Windows do not work with the current Duo/MFA setup.
This article details setting up and starting an SSH tunnel using PuTTY which will allow X2go to connect through to the target system.
We will use the fictitious system 'LinuX2go.leeds.ac.uk' as the final endpoint computer, the example client 'YourUserID' and the example port 19661 as the local port - please change these values to match your details and requirements.
The screenshots and instructions have been made using PuTTY Release 0.72 - other versions may have slightly different settings but should be similar to follow.
(1) Launch PuTTY and enter 'remote-access.leeds.ac.uk' in the Host Name section and a name for the connection in the 'Saved Sessions' box (for example - LinuX2go Tunnel 19661). Ensure SSH is selected and the Port (here) is 22. Then click the Save button.
(2) In the 'Category' side bar scroll down, expand '+SSH' and select Tunnels
(3) Enter your chosen port (for example 19661) in the Source port section and your endpoint system (for example LinuX2go.leeds.ac.uk in the Destination box) - include ':22' at the end of the address and click 'Add':
(4) Optional - you may wish to include a 'keepalive' option for your tunnel to stop it being closed down through lack of activity. Click on 'Connection' in the Category sidebar and then enter something like 30 in the 'Seconds between keepalives' box:
(5) IMPORTANT - Scroll back to the top of the Category sidebar and select Session then click on 'Save' again:
(6) Your tunnel for LinuX2go should now be configured and you can 'Open' it and enter you credentials to connect through remote-access. To Load the tunnel session in future simply select it in the Saved Sessions and then click Load (and then Open) - or simply double-click the Session to load and open it in one go:
(7) When prompted enter 'YourUserID' and then password:
(8) At the Duo prompt, enter the six digit code from your app or request a Push (1) or SMS (2) and press enter:
(9) When successful you will be presented with a regular shell session and you may then launch your X2go tunnelled session as detailed in KB0015722
Note - you must keep this session/shell running for your tunnel and X2go session to stay active. When you have finished close the window or type exit in the shell