Tip #896: Don’t get blacklisted by blasting emails from Dynamics 365

Today we welcome to the jar Steve “Mr SMB” Mordue. (And you can submit your tips too by emailing them to jar@crmtipoftheday.com.)


Don’t use Dynamics 365 to blast marketing emails because in worst case scenario either your email server will get blacklisted or you will be suspended / banned from the email service. Instead, use services of the bulk email providers.

Steve has the mic

The other day, this post popped up on my Twitter feed. It seems some poor soul got his organization on an email blacklist by sending bulk emails through CRM.

It is a common misconception, particularly with SMB customers, that CRM can be used for sending email blasts or newsletters, or even Spam. But this will cause problems like those experienced by the poster. Why?

Dynamics CRM is not an independent email system. Email sent from Dynamics CRM will go through your Exchange Server, either on-premise or online, as the user who created it. If too many of your recipients mark your message as Spam, or if your bounce rate (invalid email addresses) is too high, you run the risk of being added to an RBL (Realtime Blackhole List). This is a list of IP addresses whose owners refuse to stop the proliferation of spam. The RBL usually lists server IP addresses from ISPs whose customers are responsible for the spam and from ISPs whose servers are hijacked for spam relay. As subscribers to the RBL, ISPs and companies will know from which IP addresses to block traffic. Most traffic blocking occurs during the SMTP connection phase. The receiving end will check the RBL for the connecting IP address. If the IP address matches one on the list, then the connection gets dropped before accepting any traffic from the spammer.

Note that this not only effects your ability to send Spam, but since this went through your Exchange Server, it could affect anyone in your organization’s ability to send any email. So this is not something to mess around with. Getting yourself off of the RBL takes quite a bit of work, and in the meantime, your organization could be at a standstill.

So how do you safely send bulk email from CRM? By utilizing a third-party service like ClickDimensions, Mailchimp, Constant Contact or others. Email sent via these services goes through their servers. They spend the effort to keep their IPs off of RBLs, or take steps to get them off if they are added.

Does this mean you can Spam with abandon? Nope, each of these services will require you to confirm that you have a relationship with the people on your mailing list. If it turns out that you don’t, or too many people are unsubscribing, or marking your email as spam, they will kick you off of their service.

BTW, Spam is illegal. Each separate email in violation of the CAN-SPAM Act is subject to penalties of up to $40,654, so non-compliance can be costly. You should review this Guide before launching any sort of bulk mail campaign.

Q & A Session

Tipp Jaar: does using Hosted mail servers mitigate this risk? I’ve heard anecdotally that using O365 or gmail for your email it reduces the risk of getting blacklisted because the emails won’t all come from the same IP addresses

Steve:I guess if those servers use dynamic IPs, maybe, but I could not say for sure. I suspect, if spamming, you would probably get kicked off of those services also, unless they were servers in Russia.

Tipp Jaar: Or used by White House staff…

4 thoughts on “Tip #896: Don’t get blacklisted by blasting emails from Dynamics 365

  1. Alistair says:

    Good article but there is big difference between being blacklisted and spamming via a service and getting kicked off. You can in most circumstances get your IP unlisted within 24 hours its not the end of the world and its worth checking monthly if you are listed. Don’t ever send through exchange even if online as it is not designed for that purpose. You don’t need an email marketing solution like Click or MailChimp as you can connect queues ion CRM to email services like send grid and bulk send from CRM via a queue. Most SME need CRM to be a marketing machine and with all our hosted customers that need this feature we encourage them to send bulk email by CRM.

    • Hi Alistair,

      good point about “unblacklisting” yourself. Regarding Exchange alternatives I’d argue that if “Most SME need CRM to be a marketing mmachine” then a 3rd party integration would be preferred over a direct connection to something like sendgrid. Tracking sent emails, deliveries, opens and other interactions is important for nurturing campaigns. In addition, managing unsubscribes when using direct smtp connection would be somewhat a challenge.


    • Tobias Redfield says:

      Hello Alistar, would you mind breaking out how one would go about setting up SendGrid with a CRM queue?

      Thanks in advance

  2. Jhonnhy says:


    I was wondering if you anyone has any recommendation about sending high-volume transactional/operational email? For example for customer making purchases and receiving a payment confirmation email?

    Could Dynamics Marketing come into place, instead of using a third party like SendGrid, etc.?

    Many thanks

Leave a Reply

Your email address will not be published. Required fields are marked *