It appears that GalaSoft.MvvmLight.Extras.WPF4 have been compiled for .NET 4.5 by mistake. Surely they should be compiled for .NET 4.0?
> The primary reference "GalaSoft.MvvmLight.Extras.WPF4, Version=4.1.27.22692, Culture=neutral, PublicKeyToken=1673db7d5906b0ad, processorArchitecture=MSIL" could not be resolved because it has an indirect dependency on the assembly "System.Windows.Interactivity, Version=4.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" which was built against the ".NETFramework,Version=v4.5" framework. This is a higher version than the currently targeted framework ".NETFramework,Version=v4.0".
nic
> The primary reference "GalaSoft.MvvmLight.Extras.WPF4, Version=4.1.27.22692, Culture=neutral, PublicKeyToken=1673db7d5906b0ad, processorArchitecture=MSIL" could not be resolved because it has an indirect dependency on the assembly "System.Windows.Interactivity, Version=4.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" which was built against the ".NETFramework,Version=v4.5" framework. This is a higher version than the currently targeted framework ".NETFramework,Version=v4.0".
nic