Exceeded max defers

Problem

When sending an email, you may see the following error:

Domain example.com has exceeded the max defers and failures per hour (25/25 (100%)) allowed. Message discarded.

Symptom

• Email fails to send, or is returned, from one or more of your Volution email accounts.
• The returned email includes a Non-Delivery Report (NDR) containing the error above.

Cause

Your email account has sent more failed messages than the hourly limit allows, so outbound sending has been temporarily blocked.

This restriction exists to protect your domain’s reputation — without it, repeated failed deliveries could get your domain added to spam blacklists or blocked outright by third-party mail servers. The block clears automatically each hour.

Resolution

Blocked accounts reactivate automatically within an hour. Please wait and try sending again — no action is needed to lift the block itself, though see below to stop it recurring.

Prevention

To avoid triggering this error again, check the following:

• Identify the cause. Open Track Delivery in your hosting control panel (cPanel) and enter the affected email address, then click Run Report to see a breakdown of recent delivery failures.
• Rule out compromise. A sudden spike in failures from one mailbox often indicates a compromised account being used to send spam. Change the mailbox password immediately and run a virus/malware scan on any device that accesses that account.
• Check autoresponders and spam filters. An out-of-office autoresponder set to reply to all incoming mail will also reply to spam sent from forged or non-existent addresses — and those replies bounce, counting against your hourly failure limit. Make sure Spam Filters are enabled on your Volution hosting account so flagged spam doesn’t trigger an autoresponse.
• Clean your mailing lists. Before sending a bulk email, remove addresses that consistently bounce or no longer exist. Sending to a large number of invalid addresses is one of the most common causes of this block.
• Verify SPF, DKIM, and DMARC records. Misconfigured or missing authentication records increase the chance of legitimate mail being deferred or rejected by receiving servers, which also counts toward your failure count. Check these are correctly set up for your domain.
• Watch for automated/looped mail. Contact forms, cron jobs, or plugins that send email on a schedule or in response to triggers can silently generate large volumes of failed mail if misconfigured — worth checking if the failures aren’t tied to a specific mailbox.