This BAOI guide provides a structured method for solving smtp 550 5.7.60 sendl as.
Avant de commencer : adaptez toujours les commandes et manipulations à votre environnement. Sur un système de production, prévoyez une backup ou un retour arrière lorsque l’action peut modifier la configuration.
Étapes à suivre
1
Collect
To identify the exact error, time time and context.
2
Limit
Identify the systems and users involved.
3
Test
Use appropriate tools or commands to confirm cause.
4
Correct
Apply a targeted and reversible correction.
5
Validate
Play the full screenplay and check the logs.
À retenir
Keep the initial state.
Avoid multiple simultaneous changes.
Document the final result.
Technical deep dive
SMTP: distinguish authentication, envelope and visible identity
Technical checkpoints
The authenticated SMTP user, MAIL FROM and From: header can be three different identities.
A Send As / sender mismatch error occurs when the server accepts authentication but rejects the requested sender identity.
Message-ID, Return-Path and Received headers help reconstruct the actual message path.
Reading a failure
Keep the full SMTP response code and compare authenticated account, envelope sender and visible From.
AUTH user@example.com
MAIL FROM:<sender@example.com>
From: Display <sender@example.com>
Topic-specific pitfalls
Changing SPF/DKIM does not fix a missing Send As permission on the server.
Testing with another sender without keeping the exact response code can hide the true scope.
How to validate
The server accepts the expected sender with the intended identity and permission.
Received message headers match the expected account and domain.
Operational context
SMTP 550 5.7.60 usually means the authenticated identity is not allowed to send as the From address. Separate authentication success from sender authorization and confirm whether the application should use Send As, Send on Behalf or its own mailbox.
Step-by-step checks
Record the authenticated account and the exact From/sender address used by the application.
Confirm the target sender exists as the intended mailbox/shared mailbox and that aliases or accepted domains are correct.
Inspect Send As/recipient permissions for the authenticated identity and account for permission propagation time after a legitimate change.
Retest with the same SMTP/authentication method and avoid “fixing” the issue by granting unnecessarily broad delegation.
Useful verification commands
Use commands only on systems you administer and capture the read-only output before making a configuration change.
A controlled message must be accepted with the intended From address, appear with the expected sender identity and no longer return 5.7.60.
Evidence to keep
Keep the SMTP timestamp/message ID, authenticated account, From address, exact 550 response and current delegation output.
Frequently asked question
Why can authentication succeed while Send As fails?
SMTP authentication proves the account identity. Send As is a separate authorization decision for the From address and can be denied even after successful authentication.