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What do I do when I receive Spam?

November 29th, 2018

Even though you may using our anti-spam system correctly, it is possible you are still receiving spam. This page explains the steps to determine why you are still receiving spam messages, and how best to resolve this issue.

Check whether your MX records are correct

To prevent spam effectively, your MX records should ONLY contain those of the filtering servers, no other mail servers. If you leave the old MX records pointing to your own mail server, spammers will attempt to deliver spam directly, thus bypassing the spam filters. You can look up your domain MX records here.

Analyze the spam email header

Email headers show detailed information about the origin of a message and the various systems it passed through. Simply view the email headers in your email client, and look for the line starting with “X-Recommended-Action:”, if it’s present the message was processed by our filters. You’ll also see a “X-SpamExperts-Evidence:” header (SpamExperts may be replaced with a private label name), if it says e.g. “Whitelisted” it means that we did not check the message as the sender/recipient was whitelisted in the control panel.

X-SpamExperts-Class: line missing

If you do not see a line starting with “X-Recommended-Action:” in the email headers, this means the spam message did NOT pass through our systems, and therefore could not be blocked. There are various reasons why this might have occurred:

You might not be using the SpamExperts MX records, so please check the MX records for your domain. It’s important that you only use the following SpamExperts MX records (for our Hosted Cloud): (priority 10) (priority 20) (priority 30)

You are using the correct MX records, but they have not had sufficient traffic pass through them, it being a fresh installation. After changing the MX records in your DNS, it may take up to 48 hours before this update reaches all DNS servers world-wide. During this period, email may still be delivered directly to your mail server and therefore may not be filtered yet by the SpamExperts servers. Spammers often use old DNS information, so for a short while you may still receive spam that was never scanned by our servers.

Somehow the spammer delivered directly to your destination mail server, to prevent this we recommend users to configure their firewall/mail server to only accept messages from our servers, to avoid this issue.

X-SpamExperts-Class: line says “whitelisted”
If the class line says “whitelisted”, this means that you must have added the sender or recipient email address, to their respective whitelist on your domain. Spammers always fake the sender, and try to use senders that are likely to be put on whitelists by recipients. Therefore, it’s important to never whitelist your own email address as a sender, since spammers will often send you messages that appear to originate from yourself! The whitelists should only be used to overrule the filtering technologies, if they are causing a problem for you, by rejecting senders you know are safe but inherently look suspicious. Generally our classifiers will not block your legitimate emails.

X-SpamExperts-Class: line says “ham” or “unsure”

SpamExperts combines many technologies to provide you optimal protection from “false positives”, i.e. legitimate email, marked as spam. Since we never want a legitimate email to be blocked, if you’ve received a spam message classified as “ham” or “unsure”, our system was not confident enough to block the message, and marked it as such, giving you the opportunity to release and train the filters. This can occur if the spam message appears to be from a legitimate source.

Policy concerning Forwarding-domains: if you have multiple domains that act as email forwarders for the domain you want protected by our spam filter, we will NOT block the spam messages since they originate from a forwarding server. You will need to use our MX records for such domains, and you are more than welcome to make use of our free domain aliasing functionality to protect your forwarding domains. To check which email address the message was originally directed to, please inspect the “Received:” headers. These will specify what address the message was delivered to.

Check whether you have “catch all” enabled

Spammers love to randomly generate recipients such as, to try and deliver spam to your server. If your mail server accepts all connections for any recipient, the chance of spam getting through is significantly higher. We highly recommend you disable such “catch-all”, and instead create mailboxes and/or forwarders for email addresses that do exist.

If you cannot disable the “catch-all” behavior on your destination server, you can use the “Local Recipients” feature to specify which recipients are valid in our Control Panel.

You can test whether you have “catch-all” enabled by executing the (check) “Protection status” function in the Control Panel overview, from the drop down menu beside each domain:

Still receiving spam?

It is also possible that our system simply did not detect the spam message correctly. If this occurs, please report the message to our systems as spam, so we can further train and improve our filtering technologies. All reported messages are automatically processed centrally.

If you still receive large amounts of spam, even after using our filters, and having checked all the steps mentioned above, please email us a .zip file with all spam messages in .eml or .msg formats for analysis. Please contact us for the correct reporting address.

Finally, please make sure that the messages you report as spam are indeed spam. We do not consider messages from senders that you have subscribed to in the past, as spam, since they offer an unsubscribe option. You should unsubscribe from such mailings instead, if they are no longer desired