How to tell postfix to quit sending the same mail over and over again

[T. Mohrfeldt (Liesegang GmbH)]

Hello fellow Kolab users,

I'm struggling with a serious problem here.

One of my users sent a very large e-mail (round about 32m) to a business 
partner of us. All went as expected.
But my server won't stop sending this particular mail. I already deleted 
it from the users mailbox (via bash and via roundcube) nontheless the 
floodgates are still open and roughly all 15 seconds our business 
partner receives this mail.

Till now he's a good sport about it, but I'd rather stop his agony and 
put an halt to this.

But I have no clue from which service/directory/whatever this e-mail 
gets pumped into postfix.

ANY hints where exactly to look and how I can stop this behaviour is 
HIGHLY appreciated from my side.

Server: CentOS7 System and Kolab fully patched.


With kind regards

Torben Mohrfeldt

-- 

LIESEGANG GMBH

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