diff --git a/Source/i_oplmusic.c b/Source/i_oplmusic.c
index 05af5492..a4bae663 100644
--- a/Source/i_oplmusic.c
+++ b/Source/i_oplmusic.c
@@ -34,6 +34,10 @@
 #include "../opl/opl.h"
 #include "midifile.h"
 
+#ifdef _WIN32
+#include "../win32/win_fopen.h"
+#endif
+
 // #define OPL_MIDI_DEBUG
 
 #define MAXMIDLENGTH (96 * 1024)
diff --git a/Source/i_winmusic.c b/Source/i_winmusic.c
index 9cd24712..dcf9c8c1 100644
--- a/Source/i_winmusic.c
+++ b/Source/i_winmusic.c
@@ -28,6 +28,8 @@
 #include "m_misc2.h"
 #include "midifile.h"
 
+#include "../win32/win_fopen.h"
+
 static HMIDISTRM hMidiStream;
 
 static HANDLE hBufferReturnEvent;