diff --git a/src/plugins/wp/ProverWhy3.ml b/src/plugins/wp/ProverWhy3.ml
index 61f6651c44292adfde96610c4f16a58017fa6b9b..488d62b73e39ac08519040db8ff4d184f3702059 100644
--- a/src/plugins/wp/ProverWhy3.ml
+++ b/src/plugins/wp/ProverWhy3.ml
@@ -741,7 +741,7 @@ class visitor (ctx:context) c =
             | [ th ] -> self#add_import th
             | [ th ; was ] -> self#add_import ~was th
             | _ -> why3_failure
-                     "[driver] incorrect why3.file %S for library '%s'"
+                     "[driver] incorrect why3.import %S for library '%s'"
                      opt thy
           ) (Str.split regexp_com opt)
       in