Port 80 is being used by SYSTEM (PID 4), what is that?

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?

Solution 1:

A new service called "Web Deployment Agent Service" (MsDepSvc) can also trigger "System" with PID=4 to listen on port 80.

Solution 2:

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.

Solution 3:

Also, try stopping "SQL Server Reporting Services (MSSQLSERVER)", that apparently defaults to 80. I did that and port 80 freed up. PID identified the culprit as "System", but apparently that System can mean multiple things.

Solution 4:

I had the same problem. Could fix it by stopping the World Wide Web Publishing Service under running services.