diff --git a/ports/protobuf/CONTROL b/ports/protobuf/CONTROL
index 192b57f96e..83b672b3f8 100644
--- a/ports/protobuf/CONTROL
+++ b/ports/protobuf/CONTROL
@@ -1,4 +1,4 @@
 Source: protobuf
-Version: 3.3.0-3
+Version: 3.4.0
 Build-Depends: zlib
 Description: Protocol Buffers - Google's data interchange format
\ No newline at end of file
diff --git a/ports/protobuf/portfile.cmake b/ports/protobuf/portfile.cmake
index 83f9e1e1da..84e2c9b651 100644
--- a/ports/protobuf/portfile.cmake
+++ b/ports/protobuf/portfile.cmake
@@ -92,12 +92,12 @@ else()
     protobuf_try_remove_recurse_wait(${CURRENT_PACKAGES_DIR}/debug/bin/protoc.exe)
 endif()
 
-foreach(FILE ${CURRENT_PACKAGES_DIR}/include/google/protobuf/arena.h ${CURRENT_PACKAGES_DIR}/include/google/protobuf/stubs/port.h)
+foreach(FILE ${CURRENT_PACKAGES_DIR}/include/google/protobuf/stubs/platform_macros.h)
     file(READ ${FILE} _contents)
     if(VCPKG_LIBRARY_LINKAGE STREQUAL dynamic)
-        string(REPLACE "defined(PROTOBUF_USE_DLLS)" "1" _contents "${_contents}")
+        string(REPLACE "\#endif  // GOOGLE_PROTOBUF_PLATFORM_MACROS_H_" "\#define PROTOBUF_USE_DLLS 1\n\#endif  // GOOGLE_PROTOBUF_PLATFORM_MACROS_H_" _contents "${_contents}")
     else()
-        string(REPLACE "defined(PROTOBUF_USE_DLLS)" "0" _contents "${_contents}")
+        string(REPLACE "\#endif  // GOOGLE_PROTOBUF_PLATFORM_MACROS_H_" "\#define PROTOBUF_USE_DLLS 0\n\#endif  // GOOGLE_PROTOBUF_PLATFORM_MACROS_H_" _contents "${_contents}")
     endif()
     file(WRITE ${FILE} "${_contents}")
 endforeach()