First of all, open the MS Outlook application and tap to File tab. Now, click to add an account to start account setup.
Choose Manual setup or additional server types and tap to next.
From the choose service page, you should choose IMAP or POP and tap next.
In the given text fields, enter the email address and name, and from account type, select POP3.
In the incoming mail server field, enter inbound.att.net, and in the outgoing mail server field, enter outbound.att.net. From the logon information section, re-enter the email address in the username field and enter the sign-in password into the password field. After filling in the details, tap to more settings.
After that, choose the outgoing server field and select the “my outgoing server requires authentication” checkbox.
Select the Advanced tab and check this server requires an encrypted connection, and enter 995 in the incoming server field.
For the outgoing server field, enter 465 and from the drop-down menu “use the following type of encrypted connection” and choose to SSL.
Choose OK and tap next to start the configuration of the mailbox. Tap on Finish and tap to click to exit the wizard.