I have a netgear dg834g router and 2 PCs on my home network. I have forwarded a range of ports to my main PC, which it does no problem. The problem is when I log onto grc.com on my laptop (the other comp)and probe the range of ports I have forwarded it shows them as only being close on this comp as well (the rest are still stealthed). It seems to be forwarding the ports to both computers eventhough I have only specified the IP address of my main computer. Any suggestions, as to what I may be doing wrong, much appreciated.....

You are doing nothing wrong - all is well. Remember, when you are on either computer all of your traffic is running through the router. To put it simply: When you visit grc.com (or any site) the request first goes to your router, then the router makes a request to grc.com. Grc.com only sees the request coming from the router, not your computer. When the web page comes back your router will then direct it back to the computer that requested it. So when you ask GRC to scan your ports, it sees this request coming from your router - not you PC. So the results will always be the same from any PC connected to the same router. Michael J

Oh thanks that makes sense now, glad there's nothing wrong with my router. Is there any test available to make sure the computer the ports are being forwarded to is the only one on the network with these ports open?

Nevermind, just realised the only way to do it would be to run the application on the other PC and see if it works am I right?