diff --git a/src/f9/f90100.cpp b/src/f9/f90100.cpp
index dd835a268..4abb75297 100644
--- a/src/f9/f90100.cpp
+++ b/src/f9/f90100.cpp
@@ -3,7 +3,7 @@
 #include "lffiles.h"
 #include "isam.h"
 #include "mov.h"
-#include "f1lib.h"
+#include "../f1/f1lib.h"
 #include "../fp/fplib.h"
 #include "urldefid.h"
 #include "progind.h"