diff --git a/lib/bind9/win32/libbind9.vcxproj.in b/lib/bind9/win32/libbind9.vcxproj.in
index c0fe97c4ec..7edd5a7345 100644
--- a/lib/bind9/win32/libbind9.vcxproj.in
+++ b/lib/bind9/win32/libbind9.vcxproj.in
@@ -82,7 +82,7 @@
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>@INTRINSIC@</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;_USRDLL;LIBBIND9_EXPORTS;%(PreprocessorDefinitions);%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <AdditionalIncludeDirectories>./;../../../;include;../include;../../isc/win32;../../isc/win32/include;../../isc/include;../../isccfg/include;../../dns/include;@LIBXML2_INC@@OPENSSL_INC@@GEOIP_INC@%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <AdditionalIncludeDirectories>./;../../../;include;../include;../../isc/win32;../../isc/win32/include;../../isc/include;../../isccfg/include;../../dns/include;../../ns/include;@LIBXML2_INC@@OPENSSL_INC@@GEOIP_INC@%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <InlineFunctionExpansion>OnlyExplicitInline</InlineFunctionExpansion>
       <WholeProgramOptimization>false</WholeProgramOptimization>
       <StringPooling>true</StringPooling>