Creating a CNAME record for any one of the domains or subdomains that you have within a hosting account will enable you to redirect it to a different domain/subdomain. The forwarded domain address will lose all its records - A, MX etc, and will take the records of the Internet domain it is being pointed to. In this light, you can't create a CNAME record to direct your domain to a third-party provider and retain a functional email service with the first provider. Additionally, it is very important to know that a CNAME record is always a string of words and never a number as it is often confused with the A record of the domain being redirected. One of the major uses of a CNAME record is to direct a domain that you own through one provider to the servers of another provider in case you have set up an Internet site with the latter. That way, the Internet site will appear under your own domain name, not under some subdomain provided by the third-party company.