Hi All, Is there any way to change framework of vs2005 to 3.5?
No. Visual Studio 2005 only supports .NET 2.0 out-of-the-box. It can be updated to support .NET 3.0.
It is possible to compile .NET 3.5 code with a Visual Studio 2008 Express Edition, or without Visual Studio 2008 using Mono and I think the Windows/.NET SDK. However these will obviously not be integrated into Visual Studio 2005.
Visual Studio 2005 only supports .NET 2.0. The format of the solution file (.sln) changed in Visual Studio 2008 to allow you to select the target .NET version.
VS2008/2010 have a visual way of setting the project setting "TargetFrameworkVersion" which makes it easier, however I have found that adding the same tag to a VS2005 project will change the target framework. You might try adding 1(one) of the following into the section of your VS C# project.
<TargetFrameworkVersion>v3.0</TargetFrameworkVersion>
<TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
<TargetFrameworkVersion>v4.0</TargetFrameworkVersion>