diff --git a/test/preferences.fl b/test/preferences.fl
index 3fc993eea..c641600a3 100644
--- a/test/preferences.fl
+++ b/test/preferences.fl
@@ -5,7 +5,7 @@ code_name {.cxx}
 gridx 5 
 gridy 5 
 snap 3
-decl {\#include <Fl/Fl_Preferences.H>} {public
+decl {\#include <FL/Fl_Preferences.H>} {public
 } 
 
 decl {\#include <stdio.h>} {public