diff --git a/g10/mainproc.c b/g10/mainproc.c
index 762fc79c8..80c660848 100644
--- a/g10/mainproc.c
+++ b/g10/mainproc.c
@@ -393,7 +393,10 @@ proc_symkey_enc (CTX c, PACKET *pkt)
             }
         }
       else
-        log_error (_("encrypted with unknown algorithm %d\n"), algo);
+        {
+          log_error (_("encrypted with unknown algorithm %d\n"), algo);
+          s = NULL; /* Force a goto leave.  */
+        }
 
       if (openpgp_md_test_algo (enc->s2k.hash_algo))
         {