Creating a CNAME record for any of the domain addresses or subdomains you've got within a hosting account will permit you to direct it to a different domain/subdomain. The forwarded domain name will lose all its records - A, MX etc, and will take the records of the domain name it's being forwarded to. In this light, you simply can't create a CNAME record to redirect your domain name to a third-party company and retain a working e-mail service with the first provider. Also, it is 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 Internet domain being redirected. One of the primary uses of a CNAME record is to direct a domain that you own through one provider to the servers of some other provider assuming you have created a 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.