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IBN22's avatar
IBN22
Copper Contributor
Oct 07, 2025

I am receiving DMARC errors

Hello

Please i need your help on this issue.

Last night I started receiving DMARC and other errors when trying to send emails. I dont believe my business email is receiving messages either. 

Please help me 'fix' resolve these bounce back errors.  I did try to find the solution on my own,, but its just out of my wheelhouse.

Please help as my business is being affected by these errors and bounce backs.  

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2 Replies

  • maurobalsano's avatar
    maurobalsano
    MCT
    Dec 08, 2025

    Hi IBN22​, even without the exact bounce, a sudden "DMARC error" usually means one of these changed overnight:

    SPF/DKIM broken or missing
    1. Check your DNS has a valid SPF record for your sender, only one SPF TXT, includes the right service
    2. Make sure DKIM is enabled in your mail provider and the two DKIM CNAME/TXT records still exist

    DMARC policy too strict for your real senders
    1. If you recently set p=reject/quarantine, any service sending "as you" but not aligned like website forms, CRM, scanners, so it will fail.
    2. Temporarily set DMARC to p=none to stop blocks while you fix alignment.

    New/unknown sender started using your domain
    1. A new tool like marketing platform, ticketing, etc., may be sending without being added to SPF/DKIM.

    To move forward we still need what Zohaib_Yousuf​ asked for: the exact NDR/bounce text, your domain, and one failed message header, that will tell us whether it's SPF fail, DKIM fail, or alignment.

    Let us know with those details and we'll pinpoint the fix.

  • Zohaib_Yousuf's avatar
    Zohaib_Yousuf
    MCT
    Nov 30, 2025

    Hi,

    Please copy/paste these three things:
    The exact bounce-back error message

    (Everything—status code, explanation, error text)

    Your domain name

    (So I can check SPF, DKIM, DNS externally)

    A sample email header from one of the failed messages

     

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