553 Requested action not taken: mailbox name not allowed

Question

Trying to get some assistance trouble shooting this issue. Got a log below changed domain names but kept them specific. When I hit send it instantly comes back with the 553. Most things are defaulted on the exchange side, and we don't have many sending issues from the server, usually our firewall is what is stopping anything.

I am not seeing anything hitting my firewall, so it isn't making it out of the exchange. How can I add or update the listing to email this domain.

2023-05-19T19:35:39.445Z,Exchange,08DB418112230A36,0,,144.160.235.144:25,*,SendRoutingHeaders,Set Session Permissions

2023-05-19T19:35:39.445Z,Exchange,08DB418112230A36,1,,144.160.235.144:25,*,,attempting to connect

2023-05-19T19:35:39.446Z,Exchange,08DB418112230A36,2,182.16.9.34:24125,144.160.235.144:25,+,,

2023-05-19T19:35:39.553Z,Exchange,08DB418112230A36,3,182.16.9.34:24125,144.160.235.144:25,<,220 server.net ESMTP Service ready,

2023-05-19T19:35:39.553Z,Exchange,08DB418112230A36,4,182.16.9.34:24125,144.160.235.144:25,>,EHLO mail.domain.org,

2023-05-19T19:35:39.586Z,Exchange,08DB418112230A36,5,182.16.9.34:24125,144.160.235.144:25,<,"250 Requested mail action okay, completed OK",

2023-05-19T19:35:39.587Z,Exchange,08DB418112230A36,6,182.16.9.34:24125,144.160.235.144:25,*,,sending message with RecordId and InternetMessageId ******@domain.org

2023-05-19T19:35:39.587Z,Exchange,08DB418112230A36,7,182.16.9.34:24125,144.160.235.144:25,>,MAIL FROM:******@domain.org,

2023-05-19T19:35:39.621Z,Exchange,08DB418112230A36,8,182.16.9.34:24125,144.160.235.144:25,<,553 Requested action not taken: mailbox name not allowed,

2023-05-19T19:35:39.628Z,Exchange,08DB418112230A36,9,182.16.9.34:24125,144.160.235.144:25,>,QUIT,

2023-05-19T19:35:39.662Z,Exchange,08DB418112230A36,10,182.16.9.34:24125,144.160.235.144:25,<,221 Service closing transmission channel,

2023-05-19T19:35:39.662Z,Exchange,08DB418112230A36,11,182.16.9.34:24125,144.160.235.144:25,-,,Local

Answer 1

Hello @TempDRK !

I see that you are getting 553 when sending to a specific Domain

The 553 can be caused by :

1.       The recipient's spam filter detects the email as malicious or spam

2.       Blocklisted email address

3.       Blocklisted IP address

To resolve this you may check that the Recipient Domain is not Blacklisted , neither in the Exchange Setup there are specific Policies allowng only specific Domains

I hope this helps!

Kindly mark the answer as Accepted and Upvote in case it helped!

Regards

Answer 2

Hi @TempDRK

Are you sending from an email application?

From the log, Exchange server returns 553 Requested action not taken: mailbox name not allowed after receiving the sender email address.

Do you have some antispam applications installed on Exchange or antispam firewalls in your environment which may possibly block emails from untrusted senders?

If not, if you change the sender address to send from another domain, would it return the same error?

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