One of the most common cause for this problem is incorrect mail server settings. Please make correct email settings to fix SBCglobal mail server problems. Begin by insert imap.mail.att.net in the incoming server column for IMAP. Next, set Port to 993 and security to SSL/TLS. Lastly, enter your email address and password where required. For outgoing server: enter smtp.mail.att.net in the server column, 465 in Port, SSL/TLS in security, username, and password.
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