You must use what ATT calls a Secure mail key.

 * Server: `imap.mail.att.net`
 * Port: `993`
 * Security: **SSL/TLS**
 * Authentication: **Normal password**

 * Server: `inbound.att.net`
 * Port: `995`
 * Security: **SSL/TLS**

 * Server: `smtp.mail.att.net`
 * Port: `465` (SSL) or `587` (TLS)
 * Authentication: **Yes (same email & password)**

If your **BellSouth email account isn’t working in Mozilla Thunderbird**, it’s usually due to outdated settings or recent security changes from **AT&T**, which now manages BellSouth email services. Here’s how to fix it: ### Common Reasons & Fixes **1. Incorrect server settings** BellSouth email must use AT&T’s current mail servers. * **Incoming (IMAP – recommended):** * Server: `imap.mail.att.net` * Port: `993` * Security: **SSL/TLS** * Authentication: **Normal password** * **Incoming (POP3 – optional):** * Server: `inbound.att.net` * Port: `995` * Security: **SSL/TLS** * **Outgoing (SMTP):** * Server: `smtp.mail.att.net` * Port: `465` (SSL) or `587` (TLS) * Authentication: **Yes (same email & password)** **2. Secure Mail Key required** AT&T often blocks regular passwords in third-party apps like Thunderbird. You may need to generate a **Secure Mail Key** from your AT&T account and use that key as the password in Thunderbird. **3. Thunderbird needs an update** Make sure you’re running the latest version of Thunderbird, as older versions may fail modern security checks. **4. Antivirus or firewall interference** Temporarily disable email scanning in your security software and test again. **5. Account temporarily locked** Multiple failed login attempts can cause AT&T to block access. Logging into webmail first can sometimes unlock it. --- ### Still not working? They can help reset your email access, generate a Secure Mail Key, and verify server settings for Thunderbird. If you want, tell me whether you’re using **IMAP or POP** and your **Thunderbird version**, and I can walk you through the setup step by step.