The server “mail.DOMAIN.COM” did not recognize the following recipients:

    Hi,


    i do have a problem with my mailserver.


    One of my customers want to send newsletter mails to a bunch of people.


    But he receives the following error:


    The server “mail.DOMAIN.COM” did not recognize the following recipients:
    [...]


    What could be the problem here?


    Thanks!

    stay hungry, stay foolish!

    This is probably an invalid address, try to verify it for some other means, such as telneting and speaking SMTP to the mx destionation of creating a mail from another account.