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I am trying to launch a program which is uses port 29178 but it won't start up because it says the port is already in use. Netstat gives me this

C:\Rush>netstat -aon | findstr 29178
  TCP              LISTENING       4
  TCP    [::]:29178             [::]:0                 LISTENING       4

and process 4 is

Name                Pid Pri Thd  Hnd   Priv        CPU Time    Elapsed Time
System                4   8 154 5280    120     0:01:55.269     0:37:14.169

which tells me what exactly? Is Windows using this? How do I know what feature is using it or how to turn it off/change it?

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Turns out that I had a website setup in IIS that had a binding to this port. I'm not sure why it reports it as the System process though and not w3wp.exe.

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Some IIS components have been converted to kernel-mode drivers in recent versions, including probably the HTTP server. – grawity Jan 4 '12 at 15:04

I honestly cannot say what it is... 29178 isn't a standard port for anything I know of. As it's the system process that's listening on that port... I suspect you may have a bug on your machine... or perhaps whatever program you are trying to setup is already running... and the windows-firewall is blocking connections to it.

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