Do you have a SDK compatible with VS 2008?
SDK 3.0 is written in a newer version of VS.
I believe George already got back to you, but I will share his answer in case others are interested.
"Visual Studio is just a tool for building SDKs. The SDK itself is compatible with .Net Framework 3.5.
Internally we use the latest Visual Studio 2012, so the SDK was built with the help of it.
You can build the sources using Visual Studio 2008 if you have .Net Framework 3.5 on your machine. However you will need to make some changes in the project files to make them compatible with Visual Studio 2008. Use this guide to make appropriate changes in "*.csproj" files - http://blogs.msdn.com/b/rextang/archive/2009/07/06/9819189.aspx "
I have answered his question in dedicated thread.
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