How to Fix the “Domain has exceeded the max defers and failures per hour” Email Error

If you received this error:

Domain ilovewhc.ca has exceeded the max defers and failures per hour (25/25 (86%)) allowed. Message discarded.

It means your domain sent too many emails that bounced or couldn’t be delivered. To protect email delivery, our system temporarily blocks further outgoing emails from that domain.

Why This Happens

This typically occurs when:

• Emails are sent to invalid or non-existent addresses.
• Your messages are potentially being marked as spam by recipients.
• There's a misconfigured mail client or script sending a high volume of undeliverable emails.
• A compromised email account is sending spam.

How to fix it

Step 1: Check for Failed or Bounced Emails

If your emails are hosted with WHC:

1. Log in to cPanel.
   
2. Go to Email > Track Delivery.
   
3. Look through the delivery reports for messages marked as "Deferred" or "Failed". You can filter the search results to only show deferred of failures. 
   
4. Identify which email addresses are bouncing.
   
5. Look for patterns — for example:
   
• Are multiple emails going to the same invalid domain (like @example.com)?
  
• Are the failures happening on automated messages (like contact forms or newsletters)?
  
• Are there typos in recipient addresses?
  

Cleaning up these issues helps reduce bounce rates and restores normal sending quickly.

Step 2: Check your SPF and DKIM Settings

If your emails are hosted with WHC:

1. Log in to cPanel.
2. Go to Email Deliverability.
   
3. Locate your domain (related to the email address you're sending emails from) and check its status.
   
4. If there's a warning in the Email Deliverability Status, click Repair to automatically fix the SPF or DKIM record.
   
5. If everything shows as Valid, you're good to go.
   

Proper SPF and DKIM records help mail servers trust your emails and reduce the chance of deferrals.

Step 3: Wait for the Temporary Block to Clear

Once the bounce rate drops, the block is automatically lifted within 1 hour. You can try resending your emails after that.

Additional Tips

• Using contact forms or automated emails? Check that they're not sending to outdated or incorrect addresses.
  
• Sending to a mailing list? Make sure it’s clean and regularly updated.
  
• Noticed unusual email activity? It doesn’t hurt to change your email account passwords as a precaution.
  

Still Need Help?

If the issue keeps happening, or you’re unsure what’s causing it, reach out to our support team with the following information: 

• The full error message
  
• A few example email addresses that failed
  
• Any tools or plugins you’re using to send emails