554 Transaction Failed Spam Message Not Queued

We have a client that when they send email to one particular email domain they get the message

"554 Transaction Failed Spam Message Not Queued"

The recipient mail server IT group swears that they are seeing the messages in their filter or anything and that it must be on our end.

Watching the SMTP queue on the clients server, there is nothing getting stuck in the queue.

Everything i've seen on a google search says that its generally the recipient using an RBL thats dropping the connection between the 2 servers.

Anyone have any thoughts on this? Im at a loss.

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Comments

blargoe

If you can get the entire error message including header information it will tell you from which mail system the 554 error was generated. I wager a dollar it's on the recipient's end too, but you need the rest of the tracking info.

Hyper-Me

blargoe wrote: »

If you can get the entire error message including header information it will tell you from which mail system the 554 error was generated. I wager a dollar it's on the recipient's end too, but you need the rest of the tracking info.

The header from the actual email itself? Or would it appear in the SMTP log?

blargoe

If your customer still has the original Non-delivery report message it would all be in there.

Hyper-Me

It was the recipient server as we suspected.

They denied it and wouldnt budge, so we did a smarthost to get around it for that one domain.