The article applies to:

If for any reason you would like to modify the filtering rules, which can be used to override the spam filters that applies to your domain email service you can make modifications in the Filtering Rules section under each any of the Inbound services. 

Do note that your outbound smtp port remains unchanged and outbound smtp continues to work seamlessly with these changes.

Click Service menu item >> My Services >> select the service you would like to add Filtering rules.

From the left menu select Filtering Rules 

To create a new rule:

Click + Add Rule

Select if you would like to block or allow the a specific email or domain.

Input the filtering rule with a valid email address (wildcards supported)

To Edit a filter -
Click the Edit icon on the filter line item you would like to edit.

Make your changes and press save to complete your change.

Activate/Deactivate a filter

Click the Yes/No button to turn a filter on/off

Delete a filter

Click the Trash icon on the line item you with to remove, confirm by confirming to complete deletion

Filter Rules

These filters can be used to white list or black list domains, or email addresses. They can also be used to allow or block top level domains. This would be helpful if you wanted to block an entire Top Level Domain like .xyz or a country that may be sending you spam. 

In DuoCircle Enterprise Email Service - The rules follow this format:

Filter Rule

What does this rule do?

You can filter by a specific email address.


Filtering at the domain level. All email addresses at the domain are impacted. Note that this does not filter addresses that are subdomains of, such as * or * You need to add a filter for each level of subdomain that you          want to allow or block.


Filtering by each level of subdomain:


This is an uncommon rule - Filtering by the person's name and a wildcard at any domain.

This is an uncommon rule - Filter any email that starts with personName.*@ a certain domain. 


This is an uncommon rule - Filter email by TLD. This can be used to block all email from a country, or a domain.