Windows Firewall not allowing programs through firewall

[TypicalSpider]

I'm trying to have my firewall allow the PS3 Media Server through it, but it doesn't let me. It says "Windows firewall cannot allow PS3 Media Server to the list of exceptions." I tried other programs, same result. Tried again through the advanced settings>inbound rules, and I get this message "An error occurred while adding the rule. Error: Access is denied. Status: The rule was parsed successfully from the store" We have three computers in the house and only this one has this problem. Is there a better firewall I could be using or what?

 

[Jacee]

Look at the last answer on this page Cannot connect PS3 Media Server - Microsoft Community