Hostedemail spam and rejects

We've made a recent switch from a third-party service to something in-house to address the demand for better spam protection. With the observed benefit of meeting a better spam-free email environment, this change also affords us quicker turnarounds for new features, stability, closer alignment with our acceptable use policy, and better outbound IP protection from external blacklists.

Our development team is hard at work implementing a new feature to the new spam solution that will intelligently adjust spam policies based on everyday user interaction with our hostedemail product.

Troubleshooting guide

Ensure the user's domain's MX records are properly configured
  • For cluster A:
  • For cluster B:
    Note: Be sure to determine your cluster.

Make sure the user is not rejecting spam, but instead letting it pass to the spam folder.

Ensure that the user is not blocking the sender's IP/domain.
  1. Check the user's block list and webmail filter settings.
  2. You will want to verify that neither the sending IP, IP range, domain, or user is being blocked by the recipient.
  3. The sending IPs can be obtained from User X's received message headers, at the end of the 'Received-SPF' line
Check whether the sender Y's DMARC,DKIM, and SPF policy match what's found in user X's mail headers.
  1. Identify the sending IP, see whether you can identify the IP within the SPF TXT record of the sending domain. This online tool might make things easier
  2. Check the headers to identify whether the DKIM validation passed. This can be found on the 'X-HE-DKIM-Result' line of the header data.
  3. Check the sending domain's DMARC policy. If the DKIM or SPF validation failed, then the policy can give insight as to why the sender's message was marked as spam or rejected altogether

Customers cannot send emails to another user

It's important that we distinguish the difference between an SMTP-reject and a bounce-reject.

An SMTP-reject is when the user email client or webmail client produces a notification stating that this message cannot be sent. This means that we are not allowing the message to be sent.

A bounce-reject is when the user sends the email and later discovers a message in their inbox claiming the message was not successfully delivered. This means that the recipient email server rejected the message.

SMTP reject troubleshooting

Validate User X's status and sending capabilities

  • Is the user disabled/suspended? 
  • Is SMTP/Webmail Send disabled on the user account?
  • Did the user reach their maximum daily outbound mail ceiling?
Ask your user to save a draft of the message and review it yourself.
  • Would the contents and size of the recipient list of this message be largely considered as spam by a foreign recipient(s)?
  • Does this message meet the terms of our acceptable use policy?

Bounceback reject troubleshooting

Ask the user for a copy of their auto-generated undelivered mail bounce message. The recipient email server, at its discretion, may or may not provide a reason why the message was rejected. In the event that a reason is provided, attempt to self-serve and correct the problem.

Common reasons for rejection include:

  • The recipient does not exist
  • The recipient's mailbox is full
  • The sender did not pass SPF, DKIM, DMARC policy check
  • Sender's IP is blacklisted
    • For this scenario advise our support team. Depending on the blacklist, we may arrange to have our IP delisted.

Additional troubleshooting

If you are still struggling to determine the reason for message delivery failure email us at

For every troubleshooting case scenario please provide:

  • Your reseller ID (the name of your account at signup)
  • Your authorized user ID (what you use to login to
  • The recipient's email address
  • The sender's email address
  • The date, timestamp, and timezone of the failure
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