We have several deployments of the same assemblies with different configuration files for different environments. We package these up in to separate ClickOnce deployments with d
To run concurrent versions of a ClickOnce application, you must change the AssemblyName, and it's recommended that you also change the ProductName in the Publish properties, so you can tell in a start menu which one is which.
Click here to see how to Install Multiple Versions Concurrently