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- Start PuTTY and you should see the config screen
- Expand the SSH section of the left menu and select X11
- Check off Enable X11 forwarding
- Click back to Session in the left menu and click on Default Settings then Save
- Type in the host name you want to connect to
- Optionally fill in the "Saved Settings" box and then click save to save it in the list to connect to later
- Now click Open, if you get a message about the host key, press Yes (there are times you may not want to press yes, but that is beyond the scope of this document)
- Login to the system and type "echo $DISPLAY" to verify your tunneling is enabled. You should see something like localhost:20.0, the imporant part is the localhost and the number after the 20, it should be anything except 0. If DISPLAY returns nothing, you've done something wrong, start again.
- You may now run any command that will display back to your system, try xterm to begin with.