Blocked BAD-HEADER

[Mark Martinec]

> I just found out why I may be not getting some reports from a service I 
> am paying for:
>   Sep 26 18:45:25 z9m9z amavis[1017]: (01017-11) Blocked BAD-HEADER, 
> [31.170.123.1
>   34] [207.38.86.27] <webchaver at web556.webfaction.com> -> 
> <rgm at htt-consult.com>, M
>   essage-ID: <20180926184510_3419600 at webchaver.org>, mail_id: 
> 9nRpQDcZqcXK, Hits:
>   -, size: 59594, 1698 ms
> This is an old mailserver that I am working on updating.  Currently it 
> is running
> amavisd-new-2.6.4-2.el6.noarch

There is rarely a good reason to block a message with a bad header.
Just set the:

   $final_bad_header_destiny = D_PASS;

which is also a default amavis setting.

> there have been a number of these emails blocked  I can't see any 
> obvious setting in amavis.conf on this.
> How can I let these through to figure out what is wrong to tell them 
> what to fix?
> In typically have 50 blocked emails per day now that I fixed another 
> issue.  this source is one a week.

At log level 2 the reason is logged, e.g.:
   check_header: 8, Duplicate header field: "To"

If you quarantine such messages, the quarantined copy also receives the 
reason
in a header field, e.g.:

   X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "To"

Same goes for a passed/delivered message, or similarly in a bounce
message (if bouncing).

   Mark