If you already have it open and you see the error message, close it and reopen the program before continuing.;
, The Tools button should be in the top banner of the program. Account Settings will be in the resulting drop-down menu.



Note: In some versions of Outlook, this is found under "File" → "Info" → "Account Settings.", Once you click Account Settings, a small box with multiple tabs should show up. Choose "Email." Your email account should appear.
 More settings will launch another smaller window, with more tabs at the top. Click on Outgoing to get to the right set of settings.
 There are really only two pieces that matter, and they both need to be checked in order for Outlook to work correctly:


Check the box labeled: "My outgoing server (SMTP) requires authentication."
Click the bubble labeled: "Use same settings as my incoming mail server.", Do not, on the way, choose to "Test Account Settings." It won't work, and could undo some progress. Click "Finish" to close the other settings box, then "Close" to get out of Account Settings.


Note: Depending on your version of Outlook, these might be worded slightly differently. The important point is to not hit cancel. Look for OK, Finish, or Done when leaving settings.
 This error usually occurs when sending a message. Restart the program and try to send an email to see if it works.


If it does not, don't fear. Move on to the other possible solutions below.
Open up Outlook like normal.
Click on "Tools," then "Account Settings.",
Select the "Email" tab in Account Settings.
Choose "More Settings" from the lower-right corner, then click "Outgoing.",
Ensure your outgoing settings are correct.
Click "OK" to leave the settings and get back to your email.
Restart Outlook and try to send a message.
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