ARCHIVED: If you have problems sending mail from your IMAP mail client

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The IU Exchange Online environment does not support IMAP. See Configure your mail client for Exchange Online.

SMTP server configuration

Typically, problems sending messages indicate that your outbound (SMTP) server is configured incorrectly. If this is the case, you may receive messages similar to the following:

"The recipient dvader [or whoever is in the "To:" field] is not acceptable to your SMTP server. The message is unsendable until the recipient has been changed."
"550 <> Relaying Denied."

To correct the problem, at any Indiana University campus, in the configuration of your mail software, set the outbound (SMTP) server to:
  • If you connect to IU computing systems through most outside internet service providers (ISPs), for your IMAP software's outbound server setting, you can use either or your ISP's outgoing server setting. However, if you are required to use your ISP's SMTP server, substitute that server's name for Also, check with your ISP to determine whether its SMTP server requires authentication, and SSL or TLS.
  • If possible, use Exchange ActiveSync.

This is document aeip in the Knowledge Base.
Last modified on 2021-04-13 08:33:06.