Diagnosing What Software is Using Port 80

If you are experiencing trouble determining what software is using port 80:

  1. Run netstat -o from a command prompt. This will output a list of ports and the process ID using the port. In this example, process 4000 is using port 80.
    C:\Users\Admin>netstat -o
    

    Active Connections

    Proto Local Address Foreign Address State PID

    TCP xxx.xxx.xxx.xxx:2492 blugro5relay:2492 ESTABLISHED 5232

    TCP xxx.xxx.xxx.xxx:80 173:http ESTABLISHED 4000

    TCP xxx.xxx.xxx.xxx:80 173:http ESTABLISHED 4000

    TCP xxx.xxx.xxx.xxx:53405 cs115p1:5050 ESTABLISHED 1688

    TCP xxx.xxx.xxx.xxx:53416 bos-m001c-rdr2:https ESTABLISHED 1688

    TCP xxx.xxx.xxx.xxx:53418 chat-d03b-rdr2:https ESTABLISHED 1688

    TCP xxx.xxx.xxx.xxx:53428 mtnradsvk1200:52230 ESTABLISHED 2076

    TCP xxx.xxx.xxx.xxx:53442 pb-in-f125:5222 ESTABLISHED 4868 C:\Users\Admin>
  2. Open Windows Task Manager, switch to the Processes tab.
  3. Click View > Select Columns... and ensure that PID (Process Identifier) is selected.
  4. Sort the Windows Task Manager by the PID column to easily find the name of the process which is using port 80.