diff --git a/fhem/CHANGED b/fhem/CHANGED
index 4058b48c4..97639290b 100644
--- a/fhem/CHANGED
+++ b/fhem/CHANGED
@@ -1,5 +1,6 @@
 # Add changes at the top of the list. Keep it in ASCII, and 80-char wide.
 # Do not insert empty lines here, update check depends on it.
+ - bugfix:  70_CanOverEthernet: module crashed when UDP port was occupied
  - feature: 98_weekprofile: add reading topics - a list of topic names
  - change:  57_Calendar: new attribute, cutoffLaterThan; events without 
                 DURATION and DTEND last 1 day; several fixes (see
diff --git a/fhem/FHEM/70_CanOverEthernet.pm b/fhem/FHEM/70_CanOverEthernet.pm
index 718d223a3..8032a5fb0 100644
--- a/fhem/FHEM/70_CanOverEthernet.pm
+++ b/fhem/FHEM/70_CanOverEthernet.pm
@@ -72,6 +72,9 @@ sub CanOverEthernet_Define($$) {
 
   my $portno = 5441;
   my $conn = IO::Socket::INET->new(Proto=>"udp",LocalPort=>$portno);
+  
+  Log3 $name, 0, "CanOverEthernet ($name) - ERROR: Unable to open port 5441 for reading."
+    unless defined ($conn);
  
   $hash->{FD}    = $conn->fileno();
   $hash->{CD}    = $conn;