How do I set up the free relay on Exim (not CPanel)
Using your favorite text editor simply make the following change:
Open: /etc/postfix/main.cf
Add or Edit the following:
smarthost:
driver = manualroute
domains = !+local_domains
transport = remote_smtp
route_data = "relay.redstationmail.co.uk"
Run: service exim restart
How do I set up the free relay on CPanel
You must edit your settings in CPanel to avoid manual changes being changed by CPanel
In CPanel go to Main >> Service Configuration >> Exim Configuration Editor. Select Advanced Editor and find the textbox immediately below "Section: ROUTERSTART" then insert the following text into the textbox:
smarthost:
driver = manualroute
domains = !+local_domains
transport = remote_smtp
route_data = "relay.redstationmail.co.uk"
Finally, click save at the bottom of the page