You can set up Bellsouth email server settings for outlook by opening Outlook, Hit on File> Add Account, and then select Manual to configure server settings or additional server types. Click on the option yes on the next window. Now, enter Bellsouth's email address and name. Select IMAP/POP and hit on Next. If it’s Incoming Mail Server, enter imap.mail.att.net, and if it’s Outgoing Mail Server, enter smtp.mail.att.net. Enter your email address and password when encouraged. Select the option- More settings and check both outgoing servers (SMTP) and requires authentication. Now, you can enable SSL under the option of encrypted connection section and finally tap on the finish button. https://www.dialhumanhelp.com/bellsouth-email-server-settings/