Setting up a CNAME record for each of the domain addresses or subdomains that you've got in the hosting account will allow you to redirect it to a different domain/subdomain. The forwarded Internet domain will lose all of its records - A, MX and so forth, and will take the records of the domain address it's being pointed to. In this light, you can't create a CNAME record to point your domain to a third-party provider and maintain a working email service with the first hosting company. It's also important to note that a CNAME record is always a string of words and never a number because it is commonly mistaken for the A record of the domain name being forwarded. One of the main uses of a CNAME record is to direct a domain address that you own through one provider to the servers of some other company in case you have set up a site with the latter. By doing this, the Internet site will appear under your own domain address, not under some subdomain provided by the third-party company.