diff --git a/src/cstring.h b/src/cstring.h
index 61f08f64..fcabb2e6 100644
--- a/src/cstring.h
+++ b/src/cstring.h
@@ -33,7 +33,6 @@ SOFTWARE.
 
 #include "platform.h"
 #include "basic_string.h"
-#include "ibasic_string.h"
 #include "hash.h"
 
 #if defined(ETL_COMPILER_MICROSOFT)