Mac OS X: Mail - Messages are unexpectedly returned, undeliverable, or remain in Out Box

Address Book entries that contain commas prevent Mail messages from being delivered to the contact's email address; the message remains in the Out box and an alert appears: "The server failed to recognize any of the recipients".

This document applies to Mac OS X 10.0 through 10.2.8.

Mac OS X Mail allows you to send a message to multiple recipients by placing a comma between addresses entered in the To field. Because of this, you should avoid using commas in Address Book entries. For example, do not use "Doe, John" as the First Name of an Address Book contact (vCard). Instead, you should fill in both an entry's First and Last Name fields.

If you prefer to browse Address Book addresses in a Last Name, First Name format:

  1. Open Address Book.

  2. Select the card(s) that you wish to view in this manner.

  3. Select Card > Swap First/Last Name.

Alternatively, you may use a character other than a comma (for example, "Doe_John") in Address Book fields.


Related documents
61155: "Mac OS X Mail: How to Send an Email to Several People"

Published Date: Oct 10, 2016