diff --git a/hecl/extern/libpng/CMakeLists.txt b/hecl/extern/libpng/CMakeLists.txt
index b5ddafa69..49ad89341 100644
--- a/hecl/extern/libpng/CMakeLists.txt
+++ b/hecl/extern/libpng/CMakeLists.txt
@@ -2,7 +2,7 @@ if(NOT WIN32 AND NOT APPLE)
 find_library(PNG_LIB png)
 endif()
 
-#if(WIN32 OR APPLE OR PNG_LIB STREQUAL PNG_LIB-NOTFOUND)
+if(WIN32 OR APPLE OR PNG_LIB STREQUAL PNG_LIB-NOTFOUND)
 message(STATUS "Using HECL's built-in libpng")
 include_directories(${ZLIB_INCLUDE_DIR})
 add_library(png
@@ -33,6 +33,6 @@ add_library(png
 set(PNG_LIB png CACHE PATH "PNG library" FORCE)
 set(LIBPNG_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR} CACHE PATH "PNG include path" FORCE)
 
-#else()
-#find_path(LIBPNG_INCLUDE_DIR png.h)
-#endif()
+else()
+find_path(LIBPNG_INCLUDE_DIR png.h)
+endif()