# mail forwarding loop

**URL:** <https://community.ciphermail.com/t/mail-forwarding-loop/600>\
**Category:** Gateway\
**Created:** [February 21, 2018, 11:52am UTC](https://community.ciphermail.com/t/mail-forwarding-loop/600 "2018-02-21T11:52:17Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![martijn](https://dub1.discourse-cdn.com/flex017/user_avatar/community.ciphermail.com/martijn/32/127_2.png) [@martijn](https://community.ciphermail.com/u/martijn)\
**Post date:** [February 21, 2018, 11:52am UTC](https://community.ciphermail.com/t/mail-forwarding-loop/600/1 "2018-02-21T11:52:17Z")

</div>

> \> Von:Martijn Brinkers via Users \<users(a)lists.djigzo.com\>  
> \> Gesendet: Mittwoch 21 Februar 2018 09:07  
> \> An: users(a)lists.djigzo.com  
> \> Betreff: Re: mail forwarding loop  
> \>  
> \> \> after running a couple of days, the ciphermail system at a customers  
> \> \> site complains about a mail forwarding loop. The customers says that  
> \> \> they didn't change anything, which seems to be true according to the  
> \> \> timestamp of the configuration files.  
> \> \>  
> \> \> Even by running the smtpd daemon in verbose mode, I cannot figure  
> \> \> ouut, what causes the problem. It seems to occur, when the email is  
> \> \> reinjected by ciphermail (Version 3.3.1-0):  
> \> Hard to tell from the logs. It looks like this system is configured to  
> \> accept local email, i.e., user mailboxes are stored in the system. The  
> \> email is delivered to the mailboxes using the local daemon process.  
> \>  
> \> according to [Postfix manual - local(8)](http://www.postfix.org/local.8.html) the local delivery  
> \> daemon has a loop detection mechanism using a Delivered-To header.  
> \> Perhaps the message already contains a Delivered-To header?  
> \>  
> \> "In order to stop mail forwarding loops early, the software adds an  
> \> optional Delivered-To: header with the final envelope recipient  
> \> address. If mail arrives for a recipient that is already listed in a  
> \> Delivered-To: header, the message is bounced."  
> \>  
> \> Is the email forwarded from some mailbox (for example with Fetchmail?)  
> \>  
> yes, we use fetchmail to get the email via pop3 from mailbox.org. Since  
> this has been working for a couple of days, I have the suspicion that  
> mailbox.org changed something.

You should check whether the email stored at mailbox.org already has the  
Delivered-To header.

> I already used virtual\_maps to map edifact(a)DOMAIN.ag to  
> edifact(a)localhost, but this mapping obviuosly occur before the email is  
> forwarded to Ciphermail. It doesn't get decrypted because the email  
> address doesn't match.

CipherMail by default does not use the recipient address to find the  
decryption key. It tries to find the correct decryption key based on the  
public certificate used for encryption (with strict mode enabled, which  
is disabled by default, not all keys will be acceptable for a  
recipient). Could it be that the domain localhost is not an internal  
domain (and therefore email to localhost is not decrypted)?

Kind regards,

Martijn Brinkers

> **···**
>
> On 21-02-18 12:24, Stefan Günther wrote:
> 
> > -----Ursprüngliche Nachricht-----  
> > \> On 20-02-18 18:41, Stefan Günther via Users wrote:
> 
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