diff --git a/deps/rzlib/ioapi.c b/deps/rzlib/ioapi.c
index b550df3b8b..9dd881814f 100644
--- a/deps/rzlib/ioapi.c
+++ b/deps/rzlib/ioapi.c
@@ -10,8 +10,10 @@
 
 */
 
-#if (defined(_WIN32))
-        #define _CRT_SECURE_NO_WARNINGS
+#ifdef _WIN32
+#ifndef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS
+#endif
 #endif
 
 #include "ioapi.h"
diff --git a/msvc/RetroArch-360/RetroArch-360.vcxproj b/msvc/RetroArch-360/RetroArch-360.vcxproj
index 722fcb9c44..9b2a2d4cb2 100644
--- a/msvc/RetroArch-360/RetroArch-360.vcxproj
+++ b/msvc/RetroArch-360/RetroArch-360.vcxproj
@@ -317,6 +317,7 @@
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <PreprocessorDefinitions>NDEBUG;_XBOX;LTCG;%(PreprocessorDefinitions);HAVE_XINPUT2;_CRT_SECURE_NO_WARNINGS;RARCH_CONSOLE;HAVE_RMENU_XUI;HAVE_MENU;HAVE_NETPLAY;HAVE_SOCKET_LEGACY;HAVE_ZLIB;HAVE_RARCH_EXEC;HAVE_LIBRETRO_MANAGEMENT;D3DCOMPILE_USEVOIDS;HAVE_GRIFFIN;HAVE_HLSL;HAVE_VID_CONTEXT;HAVE_D3D9;RARCH_INTERNAL;_XBOX360;HAVE_FBO;HAVE_SCREENSHOTS;WANT_MINIZ;SINC_LOWER_QUALITY;HAVE_XAUDIO;WANT_RPNG</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(SolutionDir)\..\deps\rzlib;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
     <Link>
       <GenerateDebugInformation>true</GenerateDebugInformation>
@@ -777,4 +778,4 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
-</Project>
+</Project>
\ No newline at end of file