Emails (sent via Office 365) landing in junk folders

Discussion in 'IT & Internet' started by K0608, Sep 2, 2021.

  1. K0608

    K0608 Full Member

    186 6
    Hi, a number of clients have informed me that my emails are occasionally landing in their junk folders, which is leading to missing out on business and a major headache. I use Office 365 to send my emails and would have thought that given it's a paid-for service, that they should be doing their best to ensure deliverability.

    I've tried a few email hosts over the years, from the one that comes with our web hosting, Zoho, and now Office 365, and eventually, this problem always seems to come about.

    Here are the results from a couple of email checking services:

    Is there anything I can be doing to help with the deliverability?

    Microsoft help suggested that I get an email header from one of my clients that had one of my emails land in their junk folder, but that's easier said than done!
    Posted: Sep 2, 2021 By: K0608 Member since: May 22, 2017
  2. fisicx

    fisicx Moderator
    Verified Business ✔️

    35,094 10,710
    Have you tried using a different email client?
    Posted: Sep 2, 2021 By: fisicx Member since: Sep 12, 2006
  3. forevergroup

    forevergroup Full Member

    97 12
    Microsoft are a law unto themselves for email delivery unfortunately.

    They recently blacklisted one of our servers from emailing Microsoft customers entirely - and that was from an IP on their own Azure service and the only person using that IP address for mail was a very small client with a single mailbox. Lots of people with similar problems.

    However, in this case it looks like it's a content-based junk filter based on heuristics rather than email delivery mechanisms.

    My nose for this kind of thing recently (and it's just a hunch) is that Microsoft are being less tolerant of automated messaging from domains that are themselves linked to Microsoft 365. I've seen similar spam rejection and junk issues for example if sending on behalf of our primary M365 domain but using a third-party SMTP service allowed under SPF.

    Unless you're using an internal service like Dynamics, I'd be loathe to use M365 itself for sending automated outbound mail from the same domain. Do you get a similar result if you spin up a subdomain and use an alternative sending service to send out the mails?
    Posted: Sep 2, 2021 By: forevergroup Member since: Sep 12, 2020
  4. zigojacko

    zigojacko Verified Business ✔️

    3,749 1,212
    Office 365 is just an interface to manage your email. Who is the actual provider of the email for your domain?

    Looking at your test, it shows this domain:

    Who's mail server are you using for sending email from this domain? That's where you can improve your email deliverability, notably with SPF, DKIM signature and DMARC.

    Or is that through Microsoft? Or are you pointing your domain's MX records to Office 365's mail servers? I assume the latter.

    Ultimately, if your email address has been marked as spam/junk a lot in the past, then there won't be much you can do about this as your email domain score will be poor.

    Microsoft as a whole are a nightmare for email deliverability and blacklisting server IP addresses. I'd perhaps consider using an alternative mail server and compare deliverability.
    Posted: Sep 2, 2021 By: zigojacko Member since: Dec 7, 2009
  5. transcom

    transcom Full Member

    8 0
    Its likely to be the recipient mailserver that is stopping delivery or marking the content as spam, so you would need to get a copy of the header, its pretty easy in outlook.

    Alternatively, send the same email to two different systems and see if both are stopped.

    If your server is on a blacklist, you can check this online with , however, as the email is just junked and not stopped, it probably wont be, or, wont be on all.
    Posted: Sep 2, 2021 By: transcom Member since: Apr 17, 2013
  6. James (iimttd)

    James (iimttd) UKBF Newcomer

    3 2
    Your DMARC settings are incorrect. If you can find out what O365 needs these set to, you can then log into wherever your domain is registered and add these settings in DNS.

    The DMARC is there as a way of making sure your emails is who it says its from... With email I could send an email from your address without ever logging in to your account, these days security is a little better but modern email system receive the email from you and then compare to the data associated with your domain, if the little bits of secure data match then the email passes the spam filter. I can say with 99% certainty that's what causing your issues.
    Posted: Sep 15, 2021 By: James (iimttd) Member since: Sep 13, 2021
    • Thanks Thanks x 2
  7. K0608

    K0608 Full Member

    186 6
    Thanks for the reply! I sent an email to mail-tester, the results are here: This seems to suggest that DMARC is set correctly, but I appreciate that this is a free tool and not necessarily that accurate.
    Posted: Sep 15, 2021 By: K0608 Member since: May 22, 2017