Creating a CNAME record for any one of the domain addresses or subdomains you've got within a hosting account will permit you to redirect it to a different domain/subdomain. The forwarded domain address will lose all of its records - A, MX and so forth, and will take the records of the Internet domain it is being pointed to. In this light, you cannot set up a CNAME record to forward your domain to a third-party company and maintain a working e-mail service with the first provider. It is also important to note that a CNAME record is always a string of words and not a number as it's generally mistaken for the A record of the domain being redirected. One of the main uses of a CNAME record is to point a domain that you own through one provider to the servers of some other company assuming you have created an Internet site with the latter. In this way, the site will appear under your own domain address, not under some subdomain provided by the third-party company.