I wanted to register a domain with No-Ip and clicked the Sign Up button on their homepage. I entered my desired domain name (I won't publish it until I get this resolved, to prevent "domain theft"), then clicked Add my domain. I completed the order form, and waited 72 hours like it said, but my domain is still not active. Any help? Did I register my domain correctly?
First, do a WHOIS lookup of your domain name to see if it's listed as registered. If it's not registered but you received a confirmation of the order by email, contact your registrar for support.
If the domain is registered, it sounds like you haven't pointed the domain to a server yet, which is why you're not seeing a website when you visit the domain in your browser.
To point the domain to your home computer, follow these instructions from no-ip.
To point the domain name to a web server elsewhere, first purchase web hosting from a hosting company (search for 'shared hosting'). The welcome email from the web host will contain two or more 'nameservers', as well as an IP address. You need to enter the nameservers or the IP address in the no-ip control panel (depending on what options they give you there) to point the domain name to the web server.