Being that Cpanel, WHM, and Webmail use non-standard ports... You may have issues trying to access these interfaces from remote machines that block their ports. ie, when you are work/office or somewhere remote that doesn't have these ports open.
To work around this issue, you can setup these services on a standard port 80 port via a subdomain.
The easiest way with accomplish this is using this URL: http://www.cpanelproxy.net/autoinstall
*Keep in mind that if you don't have access to the "WHM" interface (reseller or dedicated server), please don't bother installing this interface as it will not work for you without a valid username/password that provides you with the access to this resources. All users have access to Cpanel & Webmail.
