ATT.net email settings can be updated easily using this guide.
Changing your account settings is as simple as selecting a file.
By tapping the account, you can change the AT&T email address.
Verify your POP and IMAP settings.
After that, type in the full name of the user.
If you want to remember your password, fill out the password field with the secure mail key.
Upon clicking next, your account settings will be tested.
Once you have finished the application, close it.
Verify or update AT&T email settings
Already have your email set up, but want to update your email account with your secure mail key? Here’s what you have to do:
Select File > Account Settings.
Choose your AT&T email account and then select Change.
Confirm or enter the following IMAP or POP settings:
Incoming server: imap.mail.att.net (IMAP) or inbound.att.net (POP3)
Outgoing mail server: smtp.mail.att.net (IMAP) or outbound.att.net (POP3)
Check or enter your User Name (full AT&T email address).
In the password field, enter your secure mail key and select the Remember password checkbox.
Select Next. Outlook will test your account settings.
Select Close, then Finish.