mail sending problem in using smtp

Posted on 2011-05-12
Last Modified: 2012-05-11
in my windows application, i am accessing the smtp of a server, and sending mail using the, i could able to send mail to email address which does not have a .(dot) in the address section. (ie) - i can send mail to, but when i try to send mail to smtp mail sending is failed and and error is thrown.

the error message is:
"Mailbox unavailable. The server response was: 5.7.1 Unable to relay for"
Question by:dinudany
    LVL 11

    Expert Comment

    by:Sanjay Santoki

    Based on the error issue most likely seems with the receipt end. Please be sure the email address exist on the appropriate mail server.

    Sanjay Santoki
    LVL 2

    Author Comment

    yes it exists... and it was working earlier also.
    I mean sending to email ids of was working earlier....
    Please suggest
    LVL 13

    Expert Comment

    by:Jesus Rodriguez
    Check if your SMTP server have the right to relay mails to this domain ( or try to send to another address on the same domain
    LVL 13

    Expert Comment

    by:Jesus Rodriguez
    Try to add this line to your code to configure your SMTP Delivery method (2nd line)

      Dim myMailClient As New System.Net.Mail.SmtpClient(AppSettings("SMTPHost"))
     myMailClient.DeliveryMethod = SmtpDeliveryMethod.PickupDirectoryFromIis
     myMailClient.Send(strFromEmail, strTo, strSubject, strBody)
    LVL 2

    Accepted Solution

    problem was with setting the relay server.
    LVL 2

    Author Closing Comment

    problem solved by adding the receipiants mail server address in the relay server

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