If you use a network to connect to the Internet, you might have to specify a mail proxy server. Solution: Specify a mail proxy server in your computer's System Preferences. Your account may require that you use special settings such as Secure Sockets Layer (SSL) to connect, or that you override the default port.Ĭause: Your network requires a proxy server to connect with the mail server. Note: If your account still does not work properly, check with your email service provider for details about how to configure your account in a mail application. In the Outgoing server box, enter the server name or address. If you have the address of an alternative SMTP server, enter it in your account settings. Solution: See if your ISP or network administrator can provide an alternative SMTP server to use for your POP or IMAP account. On the pop-up menu, select the authentication type, and then enter your credentials as necessary.Ĭause: Your ISP or network has a firewall that blocks connections to your email service's outgoing mail (SMTP) server. Under Outgoing server, click More Options. In the left pane of the Accounts box, select the account. If you verify that your account settings are correct, but you still can't send messages, try turning on SMTP authentication.

Some email services require authentication for their SMTP server. Solution: Turn on SMTP authentication for the POP or IMAP account. Cause: Some POP and IMAP email accounts use an outgoing mail (SMTP) server that requires authentication. Solution: Verify that Outlook is online. On the Outlook menu, make sure that Work Offline is not checked. For information about checking the status of your network connections, see Mac OS Help. On a local network, see if you can access intranet sites. Use a web browser to see if you can access web sites. Solution: Make sure that your computer is connected to the Internet or your network. Cause: Outlook doesn't have a connection to the Internet or your network. Message service can be interrupted for several reasons.

Authentication failed outlook mac