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this is a bit strange,

userA sends a email, userB gets it.

User A gets a failure notice saying that the message could not be delivered to userA, userB, userC, userd, userE, ect

the only recipient was userB, where is qmail getting all these other failed addresses, and why is it claiming that the mail failed?

this does not happen to all users, just some. deleting and recreating th euser does not stop the behaviour, reinstalling qmail-psa and recreating the queues does not stop it.

here is a snippet

From: []

Sent: Tuesday, November 13, 2007 4:26 PM
Subject: failure notice

Hi. This is the qmail-send program at
I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.

Sorry, I couldn't find any host named (#5.1.2)

<>: does not like recipient.
Remote host said: 550 Mailbox does not exist Giving up on

<>: does not like recipient.
Remote host said: 550 MAILBOX NOT FOUND
Giving up on

<>: does not like recipient.
Remote host said: 550 5.1.1 <> is not a valid mailbox Giving
up on

<>: does not like recipient.
Remote host said: 550 Recipient rejected Giving up on

<>: does not like recipient.
Remote host said: 550 5.7.1 <>...
H:MXB<>Connection refused due to abuse Giving up on

Sorry, I couldn't find a mail exchanger or IP address. (#5.4.4)

<>: does not like recipient.
Remote host said: 550 unknown Giving up on

<>: does not like recipient.
Remote host said: 550 is not a valid user Giving up on

----------------------------------------------Many more addresses snipped--------------

From: "Rochelle" <>
To: "'Gordene Rodrigues'" <>
Date: Tue, 13 Nov 2007 16:25:38 -0800
MIME-Version: 1.0
Content-Type: multipart/related;
X-Mailer: Microsoft Office Outlook, Build 11.0.5510
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198
Thread-Index: AcgmUi7FXysH+WA0RkOYPYl6cUCikQAAYTtQ
In-Reply-To: <>
share|improve this question

This looks like a spam case: Someone is pretending that he is sending mail from your email addresses so when target email servers return their error they send the replies to your userA. Do a check for several email messages of that kind and find if Users B,C .. etc. had really sent those messages (which received the errors). If they hadn't sent them then I am right.

share|improve this answer
I tried to check as many messages as I could, but let say, you send me an email from to, and then you will receive an email from Mailer-Daemon saying that, your email was not able to be delivered to as does not exist. Actually you have never sent an email to just to and email has been delivered fine. I checked the mail queue, and there are like 100 Mailer-Daemon emails generated per hour. – Big_M Jun 23 '14 at 16:37
Ok, lets do some tests: – moo Jun 23 '14 at 16:48
I am not sure why do you wanna do that, since user C does not exist. As you can see in the transcript, lets say, this email does not exist, however I will send an email to this recipient and see the results and post them here. – Big_M Jun 23 '14 at 16:50
Got the bounce back straight away : <>: does not like recipient. Remote host said: 550 5.1.1 <>... User unknown Giving up on --- Below this line is a copy of the message. – Big_M Jun 23 '14 at 17:01
1. try to send a simple email from UserB to UserC (in your own domain) and see what you 'll get. 2. try to send a mail from to some non existent mailbox but existent domain ( example - to 3. try to send an email from to non existent domain and mailbox ( example - to See what you'll get... – moo Jun 23 '14 at 17:03

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