diff --git a/fhem/FHEM/57_CalDav.pm b/fhem/FHEM/57_CalDav.pm
index e471e8a55..c69c4faec 100644
--- a/fhem/FHEM/57_CalDav.pm
+++ b/fhem/FHEM/57_CalDav.pm
@@ -47,7 +47,10 @@ sub CalDav_Process($$$) {
   my $url     = $hash->{URL};
   my $options = $hash->{OPTIONS};
   
-  return "Maybe this is the wrong way to use your calendar. Try 57_Calendar.pm instead." unless $data;
+  unless $data {
+    Log3 $hash,1,"CalDav: Maybe this is the wrong way to use your calendar. Try 57_Calendar.pm instead.";
+    return;
+  }
 
   my $d = XML::LibXML->load_xml(string => $data);