Windows XP Pro SP3 up-to-date
ZoneAlarm Pro 9.0.083.000/9.1.008.000 (per ZA Tech Support recommendation; excessive disk activity with ver. 9.1.507.000)
Please show some mercy as I'm not a network security expert. Thanks.
I've checked for open ports from time to time at ShieldsUP!, http://www.grc.com/x/ne.dll?rh1dkyd2 (Perhaps this URL varies dynamically; I don't know). It used to report all of the 1056 Service Ports in what they call "Stealth Mode", which is supposed to be as good as it gets.
Suddenly, I find that Port 135 is open. I don't know if I should be concerned or not. I've been adding new programs over time, so one of them may be responsible for this change.
In ZoneAlarm Pro, I opened the Control Center and selected Firewall->Main. Then in Custom Firewall Settings, I scrolled to the bottom and added Port 135 to Block incoming UDP ports, Block outgoing UDP ports, Block incoming TCP ports and Block outgoing TCP ports. Then I clicked "Apply". Now I see, for example, "Block incoming TCP ports: 135", but Port 135 is still open.
I can see that when I open a command window and type netstat -an. The first line returned by the netstat command reads TCP 0.0.0.0:135 0.0.0.0:0 LISTENING.
I tried disabling the DCOM service, but that screwed up 3 of my programs.
My questions: 1.) Should I be concerned? 2.) If I should be concerned, can I close Port 135 without disabling DCOM and messing up some of my programs?