Creating a CNAME record for each of the domain addresses or subdomains you've got within a hosting account will allow you to point it to a different domain/subdomain. The forwarded domain name will lose all of its records - A, MX and so forth, and will take the records of the Internet domain it's being redirected to. In this light, you cannot set up a CNAME record to direct your domain name to a third-party provider and keep a functional email service with the first hosting company. Additionally, it is very important to know that a CNAME record is always a string of words and not a number as it is generally wrongly identified as the A record of the domain name being redirected. One of the primary uses of a CNAME record is to direct a domain name which you own through one company to the servers of some other provider if you have created a website with the latter. That way, the website will appear under your own domain name, not under some subdomain provided by the third-party provider.