Setting up a CNAME record for any of the domains or subdomains you've got within a hosting account will allow you to redirect it to a different domain/subdomain. The forwarded domain name will lose all its records - A, MX and so on, and will take the records of the Internet domain it is being redirected to. In this light, you cannot set up a CNAME record to forward your domain name to a third-party company and retain a functional e-mail service with the first hosting company. It's also essential to know that a CNAME record is always a string of words rather than a number because it is often confused with the A record of the domain being forwarded. One of the main uses of a CNAME record is to forward a domain name that you own through one provider to the servers of some other company in case you have created a website with the latter. By doing this, the website will appear under your own domain address, not under some subdomain provided by the third-party company.