Please try installing this
Download: Microsoft .NET Framework 4 (Standalone Installer) - Microsoft Download Center - Download Details
also check for and apply all service packs for .net framework using window update
I deleted and reloaded my setup from the svn, and it works, you guys are missing some required dll files, which is pretty weird, but I do have every version installed however in Visual Studio my target is set to the .Net 4.0 Client profile. and my data dll is v4.0.30319 C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\Profile\Client\System.Data.dll