diff --git a/abclib.dsp b/abclib.dsp
index a1c22f6c0..06802171f 100644
--- a/abclib.dsp
+++ b/abclib.dsp
@@ -3527,6 +3527,10 @@ SOURCE=.\src\map\if\ifDec16.c
 # End Source File
 # Begin Source File
 
+SOURCE=.\src\map\if\ifDec66.c
+# End Source File
+# Begin Source File
+
 SOURCE=.\src\map\if\ifDec75.c
 # End Source File
 # Begin Source File