Advanced Troubleshoot, macOS Send-Email

The purpose of this document is to provide advanced troubleshooting for “sending email” trouble with Apple Mail, Sierra and High Sierra.

  1. You’ve already checked the basics: your Internet connection is working. You’ve quit mail (or used Force Quit if necessary), then reopened it. You’ve checked the documentation to see that your settings are correct. You’ve unchecked the Automatically manage connection settings checkbox and double-checked the settings as shown in the screenshot below. Check the Outbox. If you don’t see an Outbox, then nothing is in it - no problem. If something is in the Outbox, consider whether it contains an attachment: it may be too big to send. Or, if the email in the outbox was getting sent to numerous recipients, perhaps too many (we recommend a list of no more than 40 recips in one email). Delete the email in the Outbox or drag it to the drafts folder, and test once more sending a test to and from the troubled account. If it fails, proceed to the next steps.

  2. In Sierra and High Sierra, click on the Server Settings button, and look at the field labeled Account, immediately below Outgoing Mail Server (SMTP). In the screenshot, the account highlighted in the Accounts margin is the Jane Doe account. It is a helpful convention to name the outgoing server for the account “janedoe out”, in the event that multiple accounts are set up. In this example, if instead of “janedoe out” the field said “iCloud”, that is a problem.

    Click the field button to the right of “Account” and see whether you can find a match to janedoe on the list of servers. Each account set up should have its own outgoing email server, and be named in the way you can easily identify it with the correct account. Select the likely match, click Save, and try another test email. If that doesn’t solve it, continue below.

    High Sierra Settings

  3. If the problem persists even if there seems a match between the email address and description for the outgoing server name, we can take that a step further. Click on the button to the right of “Account” and select from the options Edit SMPT Server List.
    Edit SMTP

  4. Opening in a new window (screenshot below) shows the outgoing servers. Notice in the white box at the top there are two Server names. One is used by “Office”, the other is used by Jane Doe. The settings shown in the bottom half of the screenshot for Jane Doe look correct.

    If the account labeled “office out”, for example, is no longer in use, it would be best to remove it by highlighting it in the box in the top, and clicking the (-) beneath the box to remove the outgoing server for it. Note: never click the (-) button on the top page of the accounts, or all the email is deleted. In the SMTP Servers dialog box, only an outgoing server setting for an account is getting deleted.
    SMTP Servers