The multi-targeting feature of Visual Studio 2010 allows web developers to develop web applications targeting ASP.NET 2.0, 3.0, 3.5 and 4.0. Our earlier posts here and here describe some of the multi-targeting capabilities of Visual Studio 2010. Targeting frameworks 2.0, 3.0 or 3.5 using VS 2010 requires 3.5 Sp1 to be installed With VS 2010 Beta2, only the latest 4.0 version of the .NET framework is installed on your machine as part of the Visual Studio installation. For VS 2010 to be able to target any of the earlier frameworks 2.0, 3.0 or 3.5, the .NET Framework 3.5 Sp1 must be installed on the machine. When 3.5 Sp1 is not present If 3.5 Sp1 was not already present on your machine prior to installation of VS 2010, you will see the following...(read more) ...
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