All Domain Names have an IP address assigned to them. (For example, the
IP address for http://www.microsoft.com
Obtain the IP address for your current website from your ISP.
Login to Register.com's Domain Manager
using the username and password
that you created during the registration process along with your new
domain name. Next click Change IP and you'll be on a page on which you
can add, edit or delete IP addresses for your domain name.
Click Edit IP and change the IP address to the one that got from your
ISP. Click Yes to apply, then Yes again to confirm. The results will be
visible on the Internet within 3-24 hours.
Be sure and consult your ISP before editing IP addresses. This change
directly affects the functionality of your web site.