diff --git a/methods.go b/methods.go
index e7ff1ba..e6a9aa6 100644
--- a/methods.go
+++ b/methods.go
@@ -90,6 +90,7 @@ func (f *Forwarder) Connect(id string) (listenip string, cancel context.CancelFu
 		break
 	}
 	if lIPk == -1 {
+		return "", nil, ErrMaxConnections
 	}
 	listenip = "127.0.89." + strconv.Itoa(lIPk)
 	listenIPksMux.Unlock()