What to do if your email is blocked or bounces

Email Blocked or Bounced? How SPF, DKIM, DMARC Protect Your Business

If you run a business you need to set up your email to ENSURE DELIVERABILITY and PROTECT YOUR BRAND. 

It's surprisingly simple for someone to SPOOF your email (pretend they are you) and send phishing emails, fake payroll requests, fake payment requests, fake bank account changes or other emails that can damage your brand.   So receiving email servers are looking for a signal that your email is legitimate.

SPF, DKIM and DMARC were developed to ensure your emails get delivered not blocked or marked as SPAM, and to ensure no-one else can pretend to be you. 

If you set them up correctly you can protect your brand.  Make a mistake, or don't set them up and you'll run into problems.

If your email is bouncing or blocked when trying to reach our staff, sales or support helpdesk addresses, it's typically one of two issues:
  1. Email content or attachment is prohibited or triggering spam filters, or your email domain is flagged for SPAM
  2. Problem with your SPF, DKIM or DMARC record or similar issues with your email server set up.
If you receive a bounce message, it will tell you the problem:
  1. Mail Policy Violation - Typically a blocked attachment, URL shortener, or SPAMMY type text in the email
  2. SPF failure - your mail sender is not authorized in your SPF record (in DNS)
  3. DKIM failure - your DKIM signature is missing or not valid (in DNS)
  4. DMARC failure - your DMARC policy is missing or set to reject or quarantine and the DMARC doesn't match
  5. RBL Block List rejection - your email address or sending IP is on a blacklist

If your emails are simply going to SPAM and aren't bouncing, then our staff can check for those.  

If you receive a bounce message, the bounce message will provide details about the problem.   If it's a SPF, DKIM or DMARC error, forward that information to your IT provider or mail provider to be fixed.  If it's a "mail policy violation" reach out to the recipient and let them know what you're trying to send.

As of 2024, all the large email service providers are demanding senders set up their email records correctly to avoid deliverability problems.  You can see some background here:


For email senders, it's critical to set up email records correctly to protect your domain against hijacking, spoofing, and reputational damage.  

You can check out these popular sites for testing SPF and DMARC:



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