Why an application working in Windows7(.net 3.5)is not working in Win8(.net4.5)

Question

i have an application with TargetFrameworkVersion=v3.5

 <TargetFrameworkVersion>v3.5</TargetFrameworkVersion>

Application is working fine in windows 7 but in windows 8 i need to install .net framework 3.5 to use the application.Why i should install .net framework 3.5 even when Win8 have a default .net framework 4.5.What should i do to use the application in both Win7 and in Win8?

Answer 1

.NET 3.5 is not installed on Windows 8 by default, only .NET 4.5.

.NET 4.0/4.5 and .NET 2.0/3.0/3.5 are side-by-side installations. As such, applications built on .NET 3.5 will not run on 4.0 or 4.5. See this MSDN article for more information.

See this MSDN article about installing .NET 3.5 on Windows 8.

Answer 2

See this page for a summary of which versions of .NET are preinstalled on each version of Windows.

Unfortunately, there is no common version preinstalled on both Windows 7 and Windows 8. Windows 7 comes with 3.5.1 (includes 2.0, 3.0, 3.5) and Windows 8 comes with 4.5.