forumdestek mail sorunu

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                     The mail system 
   
  <forumdestek@donanimhaber.com>: host 77.92.152.20[77.92.152.20] said: 550 5.1.1 
      sorry, no mailbox here by that name (chkuser) (in reply to RCPT TO command) 
   
  Final-Recipient: rfc822; forumdestek@donanimhaber.com 
  Original-Recipient: rfc822;forumdestek@donanimhaber.com 
  Action: failed 
  Status: 5.1.1 
  Remote-MTA: dns; 77.92.152.20 
  Diagnostic-Code: smtp; 550 5.1.1 sorry, no mailbox here by that name (chkuser)