diff --git a/libs/win32/udns/libudns.vcproj b/libs/win32/udns/libudns.vcproj
index a4209098be..c45bee7fbf 100644
--- a/libs/win32/udns/libudns.vcproj
+++ b/libs/win32/udns/libudns.vcproj
@@ -102,6 +102,7 @@
 			/>
 			<Tool
 				Name="VCCLCompilerTool"
+				Optimization="0"
 				PreprocessorDefinitions="WIN32;NDEBUG;_LIB"
 				RuntimeLibrary="2"
 				UsePrecompiledHeader="0"