Managing User Block Lists
Spam checking is not performed on domains or email addresses that are added to the user block list, they are automatically forwarded to the recipient. Follow the steps below to manage user block list entries.
Impersonate your customer. See Impersonating a Customer.
The customer AntiSpam Engine page displays for that customer. Scroll to the User Policy Management panel, located below the Domain Management panel.
Click the edit
icon in the Options column for the user you want to edit and scroll down to the User Allow/Block List Management panel.
To add a blocked domain, click the Blocked Domains tab and click Add....
Enter the Domain in the form of example.com.
Check Include Subdomains for subdomains to also be allowed.
Enter any optional comments in the Comments field.
To add a blocked email address, click the Blocked E-mail Addresses tab and click Add....
Enter the Sender Email: in the form of user@example.com.
Enter any optional comments in the Comments field.
Click Save to save the entry or Cancel to discard.
To edit a block list entry, click the edit icon in the Options column.
To delete a block list entry, click the delete 
icon in the Options column.