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A security upgrade is coming to ATT email, so if you have certain email programs or apps, cyou’ll have to update your email settings.
By using these att email server settings, you will be able to configure your email on all mail application (Outlook, Thunderbird etc) and devices (phone, tablets etc).
Manual Settings For ATT Email Using IMAP & SMTP
As for the first step, open your email application such as Outlook, Thunderbird, or any other email application of yurchoice, on your device.
After that, go to account settings and select “Add Account” option.
Thereafter choose “Others” from the list of email providers.
Thereafter, enter your correct email address in username section followed by your email “password” in the password field.
Now go to the “Manual Setup” option and select on manual settings and enter them as told below: -
ATT email imap settings
IMAP server: “imap.mail.att.net”
Security type: None
Imap port: 993
Secure: Port=993 and Security type: SSL/TLS (Accept all certificates)
Insecure: Port=143 and security type: None (Accept all certificates)
Now enter the mentioned Outgoing (SMTP) settings and thereafter select” Next”.
ATT email smtp settings
Outgoing (SMTP) secure=Port 465
Security Type: SSL/TLS(Accept all certificates)
Outgoing (SMTP roaming server) Secure=Port 587 and security type: SSL/TLS(Accept all certificates)
Outgoing (SMTP)= Port 25 and Security type= None(accept all certificates)
Outgoing (SMTP roaming server) Insecure= Port 587 and Security type= None (accept all certificates)
Now to finish off the entire procedure, select “Done” and after performing the above-mentioned steps, you are good to use your ATT email accounts.
Read more - How Do I Set up My AT&T Email Account?