Start with the right service
An AT&T secure mail key is used by some applications that do not support OAuth. It does not replace the provider’s identity checks or recover a locked mailbox.
Configuration quick reference
| Reference | What to check |
|---|---|
| Connection and access | Use a supported OAuth client or the secure mail key method described by AT&T. |
| Account authority | Use the original provider for identity verification, account recovery, eligibility and billing. |
Official reference: AT&T secure access guidance. Check the provider’s current instructions before changing settings. Reviewed October 14, 2026.
Work through the problem
- Check whether the application supports AT&T’s OAuth sign-in.
- Test browser access before generating or changing credentials.
- Follow the secure mail key link in AT&T’s official email settings documentation. Complete all verification yourself.
- Update only the intended mail client and remove obsolete saved credentials when appropriate.
Keep a useful diagnostic record
Note the exact error, the application and version, and whether the same account works on the provider’s website. Record whether sending, receiving or sign-in fails. Remove private message content from screenshots before sharing them.
If you use POP or local folders, preserve those messages before removing an account. A new account configuration may not recover data stored only on the old device.
Choose your next step
For an app-only problem, compare authorization and settings with the official reference above. For an account restriction or failed identity check, continue with the original provider. Independent assistance cannot bypass these controls.
Related guides: IMAP, POP and SMTP · Password recovery · Email synchronization.