What does “max defers and failures per hour” mean?
If you see the message “Domain has exceeded the max defers and failures per hour”, it means that your account has exceeded the maximum allowed number of bounces (failed deliveries) per hour.
The limit is 5 Hard Bounces per hour (cPanel default setting). If you exceed it:
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Outgoing email is temporarily paused for 1 hour.
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Once the hour has passed, you can send email again, provided there are no new bounces.
What is a bounce?
A bounce means that the email you sent bounced back and did not reach the recipient.
There are two categories:
Soft Bounce (temporary problem)
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The recipient's mail server is offline.
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The recipient's mailbox is full.
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The message is too large.
Konet servers will try again. If it fails several times, it will become a Hard Bounce.
Hard Bounce (permanent problem)
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Wrong email address.
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The address does not exist.
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The domain does not exist.
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The recipient has blocked the sender.
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The antispam on our servers or on the recipient's server classified the message as spam.
Why does the 5/5 limit exist?
cPanel has set the limit 5 max defers/failures per hour as the recommended setting. It cannot be changed at account level. This protects the server and email delivery from spam or faulty mailing lists.
Prevention Tips
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Check whether you are sending spam
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In cPanel, select Track Delivery.
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Make sure all filters are enabled (Show Successes, Deferred, Failures, In-Progress).
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See whether your deliveries fail frequently.
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Check Autoresponders and SpamAssassin
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Automatic replies to spam may be counted as failures.
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If you have Professional Incoming/Outgoing Antispam, do not enable SpamAssassin.
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Clean your mailing list
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Remove incorrect or non-existent addresses.
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Use email list validation tools before your campaigns.
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Check your email signatures and images
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Do not create signatures with Microsoft Word (it inserts “junk” into the code).
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Use a clean HTML signature and images stored on your hosting.
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Frequently Asked Questions (FAQ)
What does “5/5 allowed” in the message mean?
That within 1 hour there were 5 failed deliveries (Hard Bounces) and the system temporarily blocked your outgoing email.
Isn't a limit of 5 too low?
No. It is the limit recommended by cPanel to maintain the quality and reliability of the servers.
What can I do if I need to send bulk email?
Use specialized tools such as MailChimp. Konet also has its own email marketing platform for bulk sending, and you can ask our support team about it.
How long does the block last?
Usually 1 hour. After that you can send again, provided the cause of the problem has been fixed.
How do I avoid it happening again?
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Keep your mailing list clean.
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Do not reply to spam with autoresponders.
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Use clean HTML for signatures.
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Send email only to valid addresses.
With Konet you get security, spam protection and diagnostic tools such as Track Delivery in cPanel. If the problem persists, our support team is at your disposal.