Step 1: Add a Domain in Antispamcloud portal:

click on General > Add Domain > Enter Domain name and Continue > Click on Add.

Step 2: Getting Started with Outgoing Filtering, you can refer to the below link:

https://documentation.n-able.com/spamexperts/userguide/qsg/Content/qsg/qsg-out-filter.htm

2.1. Create the Outgoing User

1. Log in to the Spam Experts Control Panel
2. Navigate to the domain you added
3. In the Outgoing panel on the Dashboard, click on Manage users
4. Add an Athenticating IP or range – Add the IP address or range of the sending mail server (log into the server to find this out) in the Authenticating IP or range tab

5. Click on Add and configure
6. Save

Step 3: Set up SPf, DKIM and DMARC records:

If you have an existing SPF record, ensure the following is added: include:spf.antispamcloud.com

If you do not have an SPF record, you need to create a TXT record (DNS record type 16):

v=spf1 include:spf.antispamcloud.com -all

Step 4: Set following Outbound Filtering Hostname for cPanel/WHM IP-based Authentication

SMTP outbound filter hostname: smtp.antispamcloud.com

4.1: Navigate to “Exim Configuration Editor” in WHM > Choose “Advanced Editor” >

Add the following to “Section: POSTMAILCOUNT” (chaning SMARTHOST to your SMTP hostname)

“`
smarthost_dkim:
driver = manualroute
domains = !+local_domains
require_files = “+/var/cpanel/domain_keys/private/${lookup{$sender_address_domain}dsearch{/var/cpanel/domain_keys/private/}}”
# Exclude null sender messages from relaying via the smarthost
condition = ${if or {{!eq{$sender_address}{}} {!eq{$sender_host_address}{}}}}
transport = remote_smtp_smart_dkim
route_list = $domain SMARTHOST::587

smarthost_regular:
driver = manualroute
domains = !+local_domains
# Exclude null sender messages from relaying via the smarthost
condition = ${if or {{!eq{$sender_address}{}} {!eq{$sender_host_address}{}}}}
transport = remote_smtp_smart_regular
route_list = $domain SMARTHOST::587
“`
4.2: Add the following in “Section: TRANSPORTSTART” then click on Save and Restart.
“`
remote_smtp_smart_dkim:
driver = smtp
hosts_require_tls = *
interface = ${if exists {/etc/mailips}{${lookup{$sender_address_domain}lsearch*{/etc/mailips}{$value}{}}}{}}
helo_data = ${if exists {/etc/mailhelo}{${lookup{$sender_address_domain}lsearch*{/etc/mailhelo}{$value}{$primary_hostname}}}{$primary_hostname}}
dkim_domain = $sender_address_domain
dkim_selector = default
dkim_private_key = “/var/cpanel/domain_keys/private/${lookup{$dkim_domain}dsearch{/var/cpanel/domain_keys/private/}}”
dkim_canon = relaxed
headers_add = “${perl{check_mail_permissions_headers}}”

remote_smtp_smart_regular:
driver = smtp
hosts_require_tls = *
interface = ${if exists {/etc/mailips}{${lookup{$sender_address_domain}lsearch*{/etc/mailips}{$value}{}}}{}}
helo_data = ${if exists {/etc/mailhelo}{${lookup{$sender_address_domain}lsearch*{/etc/mailhelo}{$value}{$primary_hostname}}}{$primary_hostname}}
headers_add = “${perl{check_mail_permissions_headers}}”
“`

Step 5: Create an email account on domain and test spam expert service.