diff --git a/lib/krb5/crypto.c b/lib/krb5/crypto.c
index a0be513e0..9d84b537d 100644
--- a/lib/krb5/crypto.c
+++ b/lib/krb5/crypto.c
@@ -2768,6 +2768,7 @@ krb5_enctype_to_string(krb5_context context,
     if(e == NULL) {
 	krb5_set_error_string (context, "encryption type %d not supported",
 			       etype);
+	*string = NULL;
 	return KRB5_PROG_ETYPE_NOSUPP;
     }
     *string = strdup(e->name);