title: How to make a .net app run on either 3.5 or 4.0/5 without asking users to install a target framework?
body: <p>I have a C# application and the target framework was 2.0. The app runs fine on Windows 7 and vista without asking users to install any framework. </p>
  
  <p>Since the coming of windows 8 the app does not run anymore. When it runs on the vanilla version of windows 8 the OS gives a message that app requires framework 3.5 and asks them to install it.</p>
  
  <p>My assumption was since Windows 8 comes with framework 4.5 and it should support older api's why should users be forced to install framework 3.5 ?</p>
  
  <p>Should I change the target of my application to be 4.5 ? and if I do so, will the app still run on windows 7 (vanilla) without asking users to have 4.5/4.0 framework ?</p>
  
  <p>Please advise, I want the app to be able to run on multiple frameworks at least 3.5 and 4.0/5 (on vista, windows 7 and 8) without asking them to install frameworks</p>
  
  <p>Thanks </p>