How did you deploy your application? Did you use ClickOnce (the publish tab in VS)?
If you are using ClickOnce, you just need to increment the version number on the Publish screen and publish a new version to the same location as the first. It will put it in a separate folder, and when the user runs the application, it will update them.
If you are using a Setup & Deployment package, it's a whole different ball of wax.
RobinDotNet
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