How to: Use Windows Installer to Deploy Applications That Can Run on Multiple Versions of the .NET Framework
If your application targets multiple versions of the .NET Framework, you can configure the Setup project to look for any version of the .NET Framework on the end-user computer. Then, the application can run on a computer that has any version (or multiple versions) of the .NET Framework installed.
The .NET Framework launch condition in the Setup project checks for the version of the .NET Framework installed on end-user computers. The bootstrapper created by the Prerequisites Dialog Box checks for and installs any missing prerequisites. Although the Setup projects can target any version of the .NET Framework, you can configure the bootstrapper to install a specific version of the .NET Framework. We recommend that the bootstrapper install a version of the .NET Framework by default so that end-users do not have to do this task manually if their computer does not have a version of the .NET Framework already installed. For more information, see Prerequisites Dialog Box.
To deploy an application that targets multiple versions of the .NET Framework
In Solution Explorer, click the setup project.
On the View menu, point to Editors and click Launch Conditions.
Right-click Requirements on Target Machine, and then click Add .NET Framework Launch Condition.
On the View menu, click Properties Window.
Change the Version property to Any.