Port 80 is being used by SYSTEM (PID 4), w

Question

I am trying to use port 80 for my application server, but when I perform netstat -aon I get:

TCP 0.0.0.0:80 0.0.0.0:0 LISTENING 4

When I look up the process in task manager, it shows PID 4 is SYSTEM, that's it. No extension... nothing. Just "SYSTEM". What's going on here?

I'm afraid to end this process, what do I do?

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UPDATE:

I've solved this through another Stack Overflow question, which had the solution to get IIS to stop listening on port 80 for a specified IP address.

Answer 1

There are many services, which can listen port 80 on windows.

Luckily you can detect and stop them all running simple console command:

NET stop HTTP

When you'll start it, you will get list first:

To avoid this problem in future go to Local Services and disable listed services.

N.B. - Some services will restart themselves immediately, just run 'NET stop HTTP' few times.

Answer 2

I just got this problem today, since it showed up after Norton requested reboot I blamed Norton.
But it wasn't Norton, I removed Norton, rebooted -> problem still there.

netstat -nao was showing that PID 4 owned my port 80 connection.

I then went to control panel, then "Turn Windows features on or off" then unchecked Internet Information Services.
Rebooted, the problem went away.
My xampp server is running ok now.

I don't ever remembering turning IIS on in the first place. I had been running many months before this happened. I still don't know what caused it in the first place. Maybe a previous windows updated enabled iis and my reboot turned it on, I don't know.

Answer 3

It sounds like IIS is listening to port 80 for HTTP requests.

Try stopping IIS by going into Control Panel/Administrative Tools/Internet Information Services, right-clicking on Default Web Site, and click on the Stop option in the popup menu, and see if the listener on port 80 has cleared.

Answer 4

For me it worked after stopping Web Deployment Agent Service.