diff --git a/aegisub/build/fftw/fftw.vcxproj b/aegisub/build/fftw/fftw.vcxproj
index bb6f108a8..88f32115f 100644
--- a/aegisub/build/fftw/fftw.vcxproj
+++ b/aegisub/build/fftw/fftw.vcxproj
@@ -48,7 +48,9 @@
         $(FftwSrcDir)\rdft\scalar;
         $(FftwSrcDir)\reodft;
         $(FftwSrcDir)\simd-support;
-        $(FftwSrcDir)\threads
+        $(FftwSrcDir)\threads;
+        $(MSBuildThisFileDirectory);
+        %(AdditionalIncludeDirectories)
       </AdditionalIncludeDirectories>
       <EnableEnhancedInstructionSet>StreamingSIMDExtensions2</EnableEnhancedInstructionSet>
       <OpenMPSupport>true</OpenMPSupport>