diff --git a/FHEM/10_MAX.pm b/FHEM/10_MAX.pm
index 63f142370..cf91f01ab 100755
--- a/FHEM/10_MAX.pm
+++ b/FHEM/10_MAX.pm
@@ -112,6 +112,7 @@ MAX_Undef($$)
 {
   my ($hash,$name) = @_;
   delete($modules{MAX}{defptr}{$hash->{addr}});
+  return undef;
 }
 
 sub