Port Forwarding?

[windygamer]

Well this is not a wireless question, but I assume this is the right place to ask it. Here's my router:
Router Model WZR-300HP
Firmware Version DD-WRT v24SP2-MULTI (07/09/12) std - build 19438

I need to set up port forwarding. And when I try to do that, the list appears blank. There is an entry but it's not filled in.
I'm using the firefox browser. 45.0.1 on windows 10.

I tried both the port forwarding and the port range forwarding and the same thing happens.

How can I set up port forwarding and see the results?

Thanks,
wg

You folks sure are concerned about spam. Even after I make an account. Really?? Seriously?? Spammers will reply to an email and still not be willing to fill out your anti-spam questions?? Sigh... here goes.. let me get out my calculator. What's the square root of.....