
Mailgun forwarding can result in your domain being treated as spam - rajivm
https://blog.rajivm.com/mailgun-forwarding-spam.html
======
alexk
Hi All,

Mailgunner here, a couple of notes:

* The case outlined in this blog post is related to incoming email forwarding feature, not Mailgun outbound sending.

* General email forwarding case does not break Mailgun's DKIM signature.

* Forwarding is tricky as long as it modifies content and we have lots of edge cases with our customers, and we are always working on improving on edge cases like this one.

* This is an edge case where the email has been forwarded from Mailchimp -> Mailgun -> Gmail and we have some conflicting content with Mailchimp's original email causing the DKIM signature failure.

* Mailgun sending pipeline team is looking at the issue to get more detail about that.

Thanks everyone!

~~~
jamestanderson
Firstly, thank you for responding.

I've also been affected by this. Any course of action that I could take? I've
been using the forwarding feature for a while, my setup is simply Cloudflare
DNS -> Mailgun -> Gmail. Would be happy to provide my domain name if you need
it!

~~~
rajivm
The real question is, can Mailgun assist with contacting Google re: affected
domains and helping clear the penalty that has been imposed.

------
teach
I had some problem with my mailgun-sent emails being marked as spam. But I was
only using the free plan, since I only send 25 mails a week or so.

I didn't have any problems with DKIM, though, or SPF. My problem was having to
use a shared IP (part of the free plan) and sometimes getting an IP that was
in one of the spam blacklists.

I'd add that [https://www.mail-tester.com/](https://www.mail-tester.com/) was
INCREDIBLY useful when I was trying to diagnose problems.

~~~
dusing
You just saved my ass with that link [https://www.mail-
tester.com/](https://www.mail-tester.com/)

Our company's email was 1.7/10 made some quick changes and now I'm 8.9

~~~
dusing
All DNS issues I thought I wouldn't have because I'm on google apps, but I
never checked. Fixed now.

~~~
pyre
I got a 9/10 sending from a Google Apps account because there is one blacklist
that has a Google IP in it! Apparently even Google's servers get blacklisted.

------
dazbradbury
As an aside, since Mailgun was bought by Rackspace, customer service,
reliability, and their ability to fix issues quickly has seemingly taken a
huge hit.

I couldn't have been happier with Mailgun a year or so ago. Currently, I have
a bug filed and reported to them that impacts our business (as well as many
others I'm sure), that has been outstanding since _July_. They still haven't
acknowledged it - and all I get is stock responses linking to their _broken_
documentation

Can anyone reccomend any alternatives? When we set up OpenRent in 2012,
Mailgun was the best. Now I'm much less convinced - any feasible alternatives
would be much appreciated.

~~~
alexk
Honestly we are the same team since Mailgun was founded, all pre-acquisition
employees are happily working on the product. The only difference is that
we've become bigger since then, and some issues may slip through the cracks
because of overall volume.

Can you send me the ticket# so I can take a look?

~~~
dazbradbury
I appreciate my experience is anecdotal, but I'm pretty sure issues used to be
read and responded to by technical members of your team - it doesn't feel that
way in the last year or so - but the acquisition may have been unrelated of
course!

Ticket: #69317 & #154021

~~~
veesahni
I agree with this one. We used to get high quality responses from technical
team members. Recent communications haven't been so great. For an example,
take a peek at Ticket #154458

In July we identified an issue where Mailgun -> ELB webhook communications are
broken under ticket #65535. This has been pending action by Mailgun's team for
4 months now.

------
DonHopkins
Another thing to do: if your mailgun email to gmail gets inexplicably marked
as spam (as opposed to DKIM failing), try creating a new fresh gmail account
and see if email to that gets marked as spam. I was using an old gmail account
and its filters were full of cat fur, which was causing stuff to randomly get
marked as spam. Spent days playing high-low game deleting parts of the message
then adding parts back in trying to figure out which words were triggering it,
and it was totally non-deterministic. But once I switched to a fresh gmail
account, it worked just fine, and nothing went into the spam folder.

~~~
danieltillett
This is what drives me crazy about avoiding spam filters. When I email out
quotes to customers (initiated by the customer of course) a certain percentage
of emails never make it. There is no rhyme or reason to it (all the obvious
things like DKIM, spf, etc are OK), it just seems to be random. Microsoft
seems to be the worst offender, but it happens on occasion with gmail and
yahoo too. Very frustrating.

~~~
jorangreef
Yes, the problem is that many MX servers do not have their spam defences setup
in the right order, especially in the case where you reply to someone who has
already emailed you:

The recipient's server should always check if your email is authenticated
(SPF, DKIM). If so, they should check if their user has emailed you in the
past, and if so they should let your email through, to prevent it being marked
as a false positive. They should try and do this even if your domain happens
to land on a single DNS blacklist (or they should use a quorum of DNS
blacklists).

------
Animats
"The lesson we learned from this is that we should separate our transactional
mail domain from our 'real email'." Yes. Especially if your "transactional
email" contains anything which could be interpreted as advertising. Many
companies interpret "transactional email" as "spamming our existing
customers". Bayesian filters interpret this as spam.

------
lobster_johnson
Out of interest, are a lot of people using Mailgun for incoming email
forwarding?

We do it because (1) Mailgun is great, and (2) it supports catch-alls, so for
example, /(.*)@foo.com/ goes to $1@bar.com. This allows our company to have
one Google Apps account, but multiple email domains. Our DNS provider, Gandi,
has email forwarding but not support catch-alls.

My understanding is that this is not precisely Mailgun's intended purpose, but
that it's fine.

~~~
thwarted
_This allows our company to have one Google Apps account, but multiple email
domains._

You can do this already with Google Apps by adding more domains to your
account. If you are using a forwarding service into your primary domain, you
run the risk of not being able to properly detect and filter spam from that
forwarder (more configuration is required on gapp's side, which isn't always
easy to get right).

~~~
lobster_johnson
We're using Mailgun for other things on that domain. Also, we're on the free
version of Google Maps, and email routing is only available for the paid
"Google Apps for Work" plan.

------
orliesaurus
I'm curious to know whether you've experienced this only on your account
and/or if you tried to replicate this on a different account? Strangely enough
I've not had problems with it although I understand the duplicate header might
be troublesome..

~~~
rajivm
I have replicated this on another Mailgun account, although that one was of
lesser importance.

------
TallboyOne
Ouch... As one who was signing up for mailgun tomorrow, thanks for pointing
that out.

~~~
rajivm
It's okay if you're just using it for outgoing mail, incoming+forwarding is
where the problem arises.

