cPanel max emails per hour, max emails per domain
To set the Value Server Wide:
You can set the value in the following file in the case of cPanel:
=====
/var/cpanel/maxemailsperhour
=====
You can set this limit at the user level by editing the following file:
=====
/var/cpanel/maxemailsperdomain
=====
Under the above mentioned location, you can create a file name which matches the domain name and you can set the limit in that file. You can just write the value ( I mean the number of emails)
If you update the above mentioned files, you need to execute the following script to update the changes.
========