diff --git a/include/ntcon/ntcon_env.h b/include/ntcon/ntcon_env.h
index 9257834..c2e3564 100644
--- a/include/ntcon/ntcon_env.h
+++ b/include/ntcon/ntcon_env.h
@@ -1,7 +1,7 @@
 #ifndef NTCON_ENV_H
 #define NTCON_ENV_H
 
-#if defined (MIDIPIX_FREESTANDING)
+#if defined (_MIDIPIX_FREESTANDING)
 
 #include <psxtypes/psxtypes.h>
 
diff --git a/project/extras.mk b/project/extras.mk
index f4a0605..03b5c36 100644
--- a/project/extras.mk
+++ b/project/extras.mk
@@ -1,7 +1,7 @@
 CFLAGS_SHARED_ATTR 	+= -DNTCON_EXPORT
 CFLAGS_STATIC_ATTR 	+= -DNTCON_STATIC
 
-CFLAGS_CONFIG 		+= -DMIDIPIX_FREESTANDING -D__NT$(HOST_BITS)
+CFLAGS_CONFIG 		+= -D_MIDIPIX_FREESTANDING -D__NT$(HOST_BITS)
 CFLAGS_CONFIG 		+= -UWIN32 -U_WIN32 -U__WIN32 -U__WIN32__
 CFLAGS_CONFIG 		+= -UWIN64 -U_WIN64 -U__WIN64 -U__WIN64__
 
diff --git a/src/ntcon_entry_point.c b/src/ntcon_entry_point.c
index bfb91b3..724c17a 100644
--- a/src/ntcon_entry_point.c
+++ b/src/ntcon_entry_point.c
@@ -1,4 +1,4 @@
-#ifdef MIDIPIX_FREESTANDING
+#ifdef _MIDIPIX_FREESTANDING
 
 #include <ntcon/ntcon.h>