The original message was received at Tue, 23 Aug 2016 13:33:39 +0530 from [35.106.231.31] ----- The following addresses had permanent fatal errors ----- dev at openvswitch.org ----- Transcript of session follows ----- ... while talking to host 105.103.207.187: >>> RCPT To:<dev at openvswitch.org> <<< 550 MAILBOX NOT FOUND