An email bounced "mail block - known spammer". Should I be concerned?

I recently sent an email broadcast to about 2800 contacts. I got 48 bounce backs. Of those bounce backs, two of them said the mail was intentionally blocked, each with a slightly different message. Here’s the messages:

mail block - known spammer
mail block - general

Other bounce messages that may be caused by the same thing are

undetermined (11x)
general bounce (24x)

A seemingly related item is that a lot of my regular emails do not get through when I’m sending from outlook. I get no bounce backs. Nothing. Many times now I’ve called a client because they haven’t replied to an email, which is when they’ll tell me it’s because they haven’t received it, not even in spam or junk folders. I often have to resort to sending clients emails from my personal Yahoo account, which is embarrassing to say the least. With an open rate under 20% on broadcasts when my entire list is former customers, I have to wonder if the same thing happens when I send with IS.

I can’t confidently do business if my emails are being filtered because they’re tagged as coming from a spammer and I’m not even alerted to the delivery failure. I don’t know a lot about these things, but I know the IP address, the web domain, and several other things can be the cause, but that those are all out of my control, except by extraordinary means. Does anyone know where I can start to investigate this kind of thing? Should I just move my email provider now (bluehost), because that’s easy and might fix it?

This issue is far from new for me, as you can see I’ve investigated it in 2015 when a string of emails were not received and I almost lost a client. How to troubleshoot unreceived emails that do not bounce back?

Is there any update or support for this? The problem is massive and it is all MSN email addresses.

For the past month, each blast I send out, now has 15% being blocked due to “mail block - known spammer”. This is terrible, these are all double opted in list members. Clearly, this is a new type of spam protection MSN has rolled out across hotmail, live, outlook, etc email addresses since they comprise the ENTIRE list of bounces for this type “mail block - known spammer”

Please advise the best way to move forward. I have been sending emails from the same address for years, I use my personal gmail address as the “From”. I did this originally to first combat MSN’s new spam filters which were blocking 50% of emails coming from my business email address. When I switched to my personal gmail, that fixed that issues. NOW, it seems MSN has done an update and I’m listed as “known spammer” to my double opted in list members who use MSN addresses.

I am going to do some more testing using different “From” addresses to get past MSN’s filter. Please post any information and advice. THank you

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I know your pain. Undelivered emails kills you. Fortunately, I have resolved some issues since posting this question.

The first is noting the difference between sending on my desktop and through Outlook vs a campaign in IS. The major problem with sending on my desktop though Outlook was my hosting provider, Bluehost, has a very bad habit of not really stopping spammers on their “shared” IPs, thus, more reputable companies and web admins are often forced to just block entire IP ranges that are under Bluehost’s control. Bluehost is shitty enough to kindly offer you an “upgrade” to less dirty IPs, when really they should have been keeping the basic IPs clean in the first place.

I resolved this issue by routing all Outlook outgoing email through AuthSMTP. It’s a separate service, but they strictly monitor spam complaints, etc, and will happily send you packing if you bring down the IP reputation. I have considered and may still route all InfusionSoft campaign emails through AuthSMTP, but current events have slowed business, so I’m sending less emails at the moment. Pricing isn’t bad, with tiers as low as $36/year and 10K emails per month at only $180/year, most small businesses can probably work with that.

Now speaking only about items that might affect you InfusionSoft campaign emails, you definitely need DKIM set up if you don’t already. Please see the main DKIM set up help file, and Can someone please dumb down DKIM for me? for more technical details. DKIM verifies IS campaign emails as explicitly from your domain name, rather than being from on behalf of

So from your question, putting your gmail in the from field needs to stop. That can only hurt your deliverability. If you don’t have your own domain and your own email at your domain, get one. It’s not an option, you need it. Then set up DKIM. This will resolve a lot of deliverability issues. If undelivereds continue or are still too high for your tastes, your can try further methods like the AuthSMTP service mentioned above.

I found an IS help file that is explicitly about this: How your from address affects email deliverability

This is all fantastic, and a full plate of work! I truly appreciate you laying down your solutions and links. We sent only from our business email addresses for 6+ years for many reasons. The switch was when the MSN addressess originally splattered their updated spam protection out, then rolled it back, then released it again.

Yes, Bluehost was one of the many originally reputable hosting companies that got bought up, swept up and consolidated into a stinking pile of garbage hosting. Hostgator suffered the same fate.

I’ll get on this and post anything I run into. Thanks again

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