Separate from IMAP prefs are the SMTP server prefs, which the email program uses to send mail.

The location varies among providers.

The iCloud Mail program uses IMAP servers to downloademail.

An illustration of the iMail IMAP and SMTP Settings.

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iCloud does not support POP mail.

Since 2017, you gotta enabletwo-step authenticationfor your iCloud account andcreate an program-specific passwordto use with IMAP.

If you don’t know your iCloud Mail password,you might reset it.