550 5.7.124: Sender not in allowed-senders list (Microsoft 365)
The group you emailed only accepts messages from a specific list of people, and you're not on it.
Blocked The address is probably fine. The problem is how the mail was sent.
What the bounce message looks like
The wording changes from one provider to another. These are typical examples:
550 5.7.124 RESOLVER.RST.SenderNotAuthorizedForGroup; sender not in allowed-senders listCommon causes
- Delivery restrictions on the group
How to fix it if you sent the email
- Ask the group owner to add you, or email a member directly.
If you manage the receiving or sending mail system
- Add the sender to the group's allowed senders, or remove the restriction.
Free tool: paste the full bounce into the bounce message decoder to get a plain-English reading of every code in it.
Questions people ask
- What does 550 5.7.124 mean?
- The group you emailed only accepts messages from a specific list of people, and you're not on it.
- Is 550 5.7.124 a hard or soft bounce?
- Blocked. The address is probably fine. The problem is how the mail was sent.
- Should I remove the address after a 5.7.124 bounce?
- No. Fix how the mail is sent; the address itself is probably fine.