If you are using PSake to build .net projects and your project has a silverlight project in it you may get the following error.

C:\Program Files (x86)\MSBuild\Microsoft\Silverlight\v4.0\Microsoft.Silverlight.Common.targets(104,9): error : The Silverlight 4 SDK is not installed. [C:\Development\Source\Main\Libraries\SilverlightShared\Silverlight.csproj]

When I encountered this I was not sure what to do since I was telling PSake that I was building with the ‘–framework 4.0; option.  However it appears that PSake does not look in the right path for the CORRECT MSBuild version.  The way that I found to solve this problem was to fully qualify the version of MSBuild that I wanted to use.  I did the following

C:\Windows\Microsoft.NET\Framework\v4.0.30319\msbuild.exe /verbosity:m $SolutionFileWithPath

I have spoken with James (the author of PSake and he thinks he can have a fix for this) but just incase he does not get it or you have this problem now at least you know how to solve it.

Till next time,