diff --git a/tests/xharness/Harness.cs b/tests/xharness/Harness.cs
index 489815d79a..55cae02f8e 100644
--- a/tests/xharness/Harness.cs
+++ b/tests/xharness/Harness.cs
@@ -194,7 +194,7 @@ namespace xharness
 		void LoadConfig ()
 		{
 			ParseConfigFiles ();
-			var src_root = Path.GetDirectoryName (RootDirectory);
+			var src_root = Path.GetDirectoryName (Path.GetFullPath (RootDirectory));
 			MONO_PATH = Path.GetFullPath (Path.Combine (src_root, "external", "mono"));
 			WATCH_MONO_PATH = make_config ["WATCH_MONO_PATH"];
 			TVOS_MONO_PATH = MONO_PATH;
diff --git a/tests/xharness/xharness.csproj b/tests/xharness/xharness.csproj
index ae5c0f9940..015b0a2b70 100644
--- a/tests/xharness/xharness.csproj
+++ b/tests/xharness/xharness.csproj
@@ -45,6 +45,14 @@
       <Variable name="MONO_ENV_OPTIONS" value="--trace=E:all" />
     </EnvironmentVariables>
   </PropertyGroup>
+  <PropertyGroup Condition=" '$(RunConfiguration)' == 'Makefile.inc' ">
+    <StartAction>Project</StartAction>
+    <StartArguments>--configure --autoconf --rootdir ..</StartArguments>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(RunConfiguration)' == 'Makefile-mac.inc' ">
+    <StartAction>Project</StartAction>
+    <StartArguments>--configure --autoconf --rootdir .. --mac </StartArguments>
+  </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
     <Reference Include="System.Xml" />