[ZendTo] Re: How to handle bounces

[Jules]

On 23/03/2012 14:40, Alexander Fisher wrote:
> On 23 March 2012 13:15, Jules<Jules at zend.to>  wrote:
>>
>> On 23/03/2012 12:41, Alexander Fisher wrote:
>>>> I have no control whatsoever over the content of the bounce message. It
>>>> is generated by the MTA (Postfix or whatever). You *may* find that
>>>> Postfix allows you to customise the contents of the bounce message to a
>>>> certain extent, but you would have to dig through the Postfix docs to
>>>> see if that is possible.
>>>>
>>>> Jules.
>>> I appreciate that the bounce is generated by postfix, it's just a
>>> shame that gmail's anti-spam system has 1. decided it looks like a
>>> bounce message and 2. decided it's spam because there's no outgoing
>>> message from gmail that it'd be a bounce for.  At least I think that's
>>> what they're doing.
>>>
>>> This is really unfortunate, because for us at least, we were probably
>>> better off before when all the bounces were delivered to me.  At least
>>> in this situation, I would see the bounce, recognise the fact that a
>>> customer had mistyped one of our user's email address and could
>>> manually get in touch with them to say try again.  On the other hand,
>>> for a large organisation where this would be impractical, the change
>>> is probably an improvement.
>>>
>>> I suppose there might be a cleverer way of handling bounces.  Perhaps
>>> a procmail script on the zendto server could process the bounce
>>> somehow and do something more funky...
>> Due to the wide variety of formatting of bounce messages generated by
>> all the different email systems in the world, doing anything automatic
>> is way beyond the scope of a system such as ZendTo. Google have tens of
>> thousands of employees, which gives them the time to do things like this.
>>> I imagine such a system could work better, but would undoubtedly
>>> involve more than just a single line of code. :)
>> Indeed!
> If some sort of tracking id was inserted into either the subject or
> body of the outgoing email, they should be somewhere in the bounce
> regardless of format shouldn't they?  Or is even that too unreliable?
> Anyway... probably too much work either way (although I might have a
> go at some proof of concept code if I get a free afternoon sometime
> soon) :)
No, it has to go in a special header and be cryptographically secure. 
One of the big ISPs has some patents pending on stuff to do a job 
similar to this, it's far from trivial to make it work.
>
> With regard to the less drastic one liner mod, if you're going to
> incorporate it into future releases, perhaps it could be made
> configurable?
> Preferably, I'd have the option to set the from address automatically
> when sending from internal to external users, but could disable this
> behaviour for email originating from outside users.
Yes, it would need to be disabled for external users as otherwise it can 
be used for "Joe-job" attacks.

Jules.

>
> Kind Regards,
> Alex
>
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Jules

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