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The CNAME record creates an alias for subdomain.yourdomain.com and points to Mibo email gateway The CNAME is needed for our click and open tracking features in order for those statistics to be routed back to your Mibo account. This will also be what your messages are signed by, so your recipients will be able to see what you have chosen for your CNAME. You set up the CNAME files that Mibo provides with your DNS host.
How to set Cname ?