--- mk/vs/Packet++.vcxproj.template
+++ mk/vs/Packet++.vcxproj.template
@@ -273,7 +273,7 @@
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\3rdParty\hash-library\md5.cpp" />
-    <ClCompile Include="..\..\3rdParty\hash-library\md5.h" />
+    <ClInclude Include="..\..\3rdParty\hash-library\md5.h" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="Common++.vcxproj">