diff --git a/build.fsx b/build.fsx
index fcf57b319d..6ab5ef81a1 100644
--- a/build.fsx
+++ b/build.fsx
@@ -482,7 +482,6 @@ let fakeStartInfo fsiargs script workingDirectory args environmentVars =
             info.EnvironmentVariables.[k] <- v
         for (k, v) in environmentVars do
             setVar k v
-        setVar "MSBuild" msBuildExe
         setVar "GIT" Git.CommandHelper.gitPath
         setVar "FSI" fsiPath)