In order for the SpamTitan Cloud servers to accept mail for your domain, you first have to add the domain to your account.

To do this log in as a Domain Group Administrator.  Go to Settings > Relay Settings and click Add.  You will be presented with the following window:

Domain:  Your email domain
Destination server: The mail server to which you want you clean, filtered mail delivered.  This will usually be the external IP address or domain name of your site, or your Office365 domain name.
Destination Port:  25 is the default SMTP port.  All mail servers will use port 25 unless configured otherwise.
Enable MX Lookup:  This option allows you to use the MX records of a different domain to identify the destination server.  This option will not be used by most SpamTitan Cloud customers.
Recipient Verification:  This feature allows the SpamTitan Cloud servers to verify if a recipient address exists.  There a re a number of methods, the one we recommend using is Dynamic Recipient Verification.  In order for Dynamic Recipient Verification to work your mail server has to be configured to reject invalid addresses.  We have guides on how to do this for various mail servers here:

Exchange 2007, 2010 and others:
Recipient Verification

Exchange 2013 & 2016:
Dynamic Recipient Verification using Exchange 2013 and 2016

RBL Checks:  This setting allows you to enable or disable Realtime Blackhole List (RBL) checks for this domain.  This test checks the IP address of all mail servers sending mail to your domain against lists of know spammer IP addresses.  This test is extremely effective at blocking spam, we strongly recommend leaving this option enabled.

SPF Checks: This setting allows you to enable or disable Sender Policy Framework (SPF) checks for this domain. This test checks the SPF record of the sending domain, to make sure the IP of the sender is allowed for the domain, and if not, rejects the mail. This test is quite effect at blocking spam, however it can cause potential false positives due to improperly setup SPF records. We recommend enabling with caution.

Greylisting: This setting allows you to enable or disable Greylisting for this domain. This temporarily rejects all mail and makes the sending server send it again after 5 minutes. This delay has many benefits, because spammers will often not retry (while legitimate servers should always reattempt to send), and if they do, the delay gives some time for their IP address to be listed on RBLs if they are a spammer. This is highly effective at blocking spam for these reasons, however it comes at the cost of mail delay (by 5-10 minutes, depending on the sending server).

Once your domain has been added you can test to see if mail can be delivered to the destination server:


Click the test button shown in the image above, enter a valid email address and click send.  The mail should be delivered to the specified address.