In this article, I have told you how to make .Net Application compatible with 32bit and 64bit window platform. By doing this you don’t need to make a setup for 32bit and 64bit windows platform separately. Let’s start.
Open your project in Visual Studio 2010. In Solution Explorer (Cltr+Alt+L), right click on your project , select properties, select build tab. Find Platform target, change it to x86 as shown in below figure.

Now build your project and run your setup on both 32bit and 64bit windows platform.