Port 554 open per scan on GRC - How can I close or stealth this port?
if you connect to the internet via a hardware firewall [Router
] you could be testing the hardware f/w [Router
] and not the PC's OS.
port 554 has to do with real time streaming protocol,
used to control media streaming, music, or video.
so i'd suspect that there is an app you have installed that is related to streaming as either a server or client,
or an apps installed for a Smartphone phone or Weather App may be responsible.
ZoneAlarm doesn't open or close ports, the app does
. this wiki page
gives a techie description and lists a number of client and server apps near the bottom. one of those, if installed, may be running as a service and keeping the ports open or showing closed.
many apps use upnp commands to open/close ports in hardware firewall transparently to the user.
the ultimate solution may be to uninstall any offending app or disable it when you are not actively using it