diff --git a/projects/openttd.vcproj b/projects/openttd.vcproj
index e47fba85f9..73e22e264f 100644
--- a/projects/openttd.vcproj
+++ b/projects/openttd.vcproj
@@ -1005,10 +1005,10 @@
 				RelativePath=".\..\src\blitter\32bpp_base.hpp">
 			</File>
 			<File
-				RelativePath=".\..\src\blitter\32bpp_optimized.hpp">
+				RelativePath=".\..\src\blitter\32bpp_optimized.cpp">
 			</File>
 			<File
-				RelativePath=".\..\src\blitter\32bpp_optimized.cpp">
+				RelativePath=".\..\src\blitter\32bpp_optimized.hpp">
 			</File>
 			<File
 				RelativePath=".\..\src\blitter\32bpp_simple.cpp">