OK, I have a Windows Forms application published using ClickOnce to
http://MyDevComputer1/DevPublishFolder/
, so the deployement link is http://MyDevCo
How to move a ClickOnce deployment is the article that goes with the video showing how to move a ClickOnce deployment.
Once all of the clients have received the new version, they will look to the new URL (and your new server) for all future updates.