Mac OS X: Mail - How to Send a Message at a Later Time
This document describes how to send an email message at a later time using the Mac OS X application Mail.
Some email clients can queue messages for later delivery without trying to send them. This is useful if you do not have a constant connection to the Internet. The Mac OS X application Mail does not have a single-button way to do this. The following alternatives may work for you.
Send the message immediately. If you have a modem connection, this may cause your modem to dial.
Send the message when your computer is not connected to a network. After a slight delay, an alert box with this message appears:
"Error This message could not be delivered and will remain in your Outbox until it can be delivered. The server "<name of mail server>" can not be contacted on port 25."
Figure 1 Cannot deliver message alert
Click Close Window. The message will be placed in your Outbox.