[Mauzen]

First of all be sure that you are using no-ip correctly. Did you set up your router for dynamic DNS correctly? To test it, you can e.g. open your console (cmd) and try "ping <your no-ip.com address>"
If the pings are successful everything is fine. If not, this either means that you didnt set up no-ip correctly, or that your router blocks pings. However, it should still resolve your ip correctly anyways. (it is displayed at the top then)

So if no-ip isnt working, try to fix this first. As I said your router has to be set up for this, there is an option for that somewhere.

But if it is working, it is the usual port forwarding problem. Common mistakes are:
Software firewall running: be sure to completely disable your windows firewall and all other firewalls for testing.
port forwarding mistage: You have to forward your desired portnumber for incoming TCP and UDP for all adresses to the same port on your local address (maybe not all of this is configurable on your router, ignore the rest then)
If you dont know your exact local address, type "ipconfig" in the cmd. Local addresses usually start with "192." or "169."

Edit: Just read in your other topic that also hamachi isnt working. Hamachi is no-ip independent, so it is either your firewall or the port forwarding.