Dennis,

That port may be used by that program but that is not a guarantee that the program is running (or has ever been run) on your computer. Almost any port can be used by any program provided it is available at the time the program wants it. Half-Life is also a known and "safe" program played by many people so it is not likely that this is related.

In respect of what has that port open you can look at the various tools on the Sysinternals website. Look for programs like Process Explorer and TCP View, for example.

http://technet.microsoft.com/en-us/sysinternals/default.aspx




>Jos,
>
>In addtition, I looked up port 27015. It is being used usually for a game called Half-Life - which I never played or installed in my machine. The other port number changes with every reboot.
>
>Thanks!
>
>Dennis
>