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=How to connect to a Mac VNC session through a tunnel using putty=

The default VNC port on Mac is 5900. On linux is often 5900 or 5901. The source port is a free and open port on your local machine. (You may need to open that port on your firewall). The 'local' radio button should be selected. Click add, go back to sessions and save the session for next time. Then login to the remote SSH server as you normal would with your userid and password:

Select Using a vnc client such as TightVNC, select locahost:50005 (or whatever local port you use):