I tried to solve this problem myself but I cannot do it. I am sorry to disturb you.
What I would like to do is to connect to the cluster computer in the lab that located inside the University from my home. The university use public-private key authentication while the lab use password authentication.
I just upgraded the operating system in my laptop from Windows 7 to Windows 10. After the upgrade, I could not tunnel through the gateway of the university. The error is "Server unexpectedly closed network connection."
I attached the log file to you privately.
Note that I tried the tunnel from inside the university but outside the lab, and the connection can be established normally. I also tried to close the firewall and then connected from my home but it did not work.
Last but not least, I am also using PuTTYPortable, and it does not work after upgraded to Windows 10 as well.
Thank you very much.