Microsoft Visual Studio 2005 support has been discontinued because Visual Studio 2005 has reached its end of support date.
Visual Studio 2005 was first released in October 2005 and was later upgraded to support NET Framework 2.0. Support for .NET Framework 3.0 is offered through Visual Studio 2005 extensions for .NET Framework 3.0.
To have access to support of .NET Framework 3.0 or later, you should use Visual Studio 2008 or later. If you perform additional work in Visual Studio 2005, you can use .NET Framework 3.0 or later because Visual Studio 2005 does not have any built-in dependency on the .NET Framework. However, you will not have access to new project and file templates and tools.
Use Visual Studio 2008 or Visual Studio 2010 instead of Visual Studio 2005. You can convert existing projects in Visual Studio 2005 to Visual Studio 2008 or Visual Studio 2010.