Deliver same E-Mail in same Mailbox only once ?

Stephan Bosch stephan at
Wed Apr 20 19:21:11 UTC 2016

Op 4/20/2016 om 7:31 PM schreef Heiko Schlittermann:
> Hi,
> Thomas Leuxner <tlx at> (Mi 20 Apr 2016 11:04:22 CEST):
>> * Christoph Adomeit <Christoph.Adomeit at> 2016.04.20 10:29:
>>> Is there a way to deliver  the same Mail in the same Mailbox only once ?
>> Yes this case is supported via an sieve extension:
>> require ["duplicate"];
>> #Deduplicate mails sent to aliases for same mailbox using the msgid
>> if duplicate {
>>       discard;
>> }
> I wouldn't do that. Message with the same message id doesn't need to be
> duplicates. See the difference between this message (I put you on BCC),
> you'll receive it via the mailing list AND directly. Depending on the ML
> configuration the messages are NOT identical.

The "duplicate" test allows more complex arguments to handle such
concerns. This way, for example, the list-id header (if present) can
also be part of the unique ID used for duplicate tracking.



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