I have a Windows Forms application developed using C# in .NET framework 3.5, Service pack 1. The application can be published based on the development database as well as th
The first thing I'd try is to go to the project properties of your Windows Forms project. In the Publish tab click on the Options button and change the "Product Name" to YourProductName_Test or something similar and see if that will allow you to install two versions side by side.
I never tried this, but I think ClickOnce apps are uniquely identified by a combination of "Publisher Name" and "Product Name" values and if that is the case this might solve your problem... Give it a shot...