diff --git a/Build/build.ps1 b/Build/build.ps1
index 417dbd56..04769f73 100644
--- a/Build/build.ps1
+++ b/Build/build.ps1
@@ -78,7 +78,8 @@ task Package -depends Merge {
   
   if ($buildDocumentation)
   {
-    exec { msbuild "/t:Clean;Rebuild" /p:Configuration=Release "/p:DocumentationSourcePath=$workingDir\Package\Bin\Net" $docDir\doc.shfbproj } "Error building documentation. Check that you have Sandcastle, Sandcastle Help File Builder and HTML Help Workshop installed."
+    # Sandcastle has issues when compiling with .NET 4 MSBuild - http://shfb.codeplex.com/Thread/View.aspx?ThreadId=50652
+    exec { .$env:windir\Microsoft.NET\Framework\v3.5\MSBuild.exe "/t:Clean;Rebuild" /p:Configuration=Release "/p:DocumentationSourcePath=$workingDir\Package\Bin\Net" $docDir\doc.shfbproj } "Error building documentation. Check that you have Sandcastle, Sandcastle Help File Builder and HTML Help Workshop installed."
     
     move -Path $workingDir\Documentation\Documentation.chm -Destination $workingDir\Package\Documentation.chm
     move -Path $workingDir\Documentation\LastBuild.log -Destination $workingDir\Documentation.log