Login to WHM:

1. Click Exim Configuration Editor
2. Check the box next to:
3. "Send outgoing mail from the ip that matches the domain name in /etc/mailips (*: IP can be added to the file to change the main outgoing interface)"
4. Save Changes
5. Then edit the file /etc/mailips
from shell and add: *: #ReplacewithnewIP#
service exim restart

Login to Shell:

1. Access the Exim configuration file:
nano /etc/exim.conf
2.Locate remote_smtp
3.The default setup will look like:

remote_smtp:
driver = smtp
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_ho stname}}+


Change to:

remote_smtp:
driver = smtp
interface = 12.14.12.14 # Change to your server IP address.
Save changes and exit.
Restart Exim

If there is an exim update when you upgrade your cPanel server you will need to re-enter the interface again.