Inspecting Which Application is Listening on Port 80

How to identify & troubleshoot why HTTP port 80 already bind, used or not available.

After installing Vertrigo (LAMP Suite) or Microsoft IIS Internet Information Services, or any other software server suite that listen to port HTTP 80, it’ll be a surprise that if some other application already already stolen port 80. Situation can be you have just installed fresh copy of web server and there is no server previously running? Question, How to check and identify which applicaiton is listening and using port 80 or 443.

The first thing today I am amazed to discover its Skype messenger that occupied port 80 and 443, so your to make sure skype will no more using port 80.  See the figure below to make sure skype’s port 80 usage is unchecked.

Now, if you having still problem or you don’t have skype installed on your system, then try to following.

Here’s a few built-in commands and how to guide that can help users to find out and identify which application or process that is already using, opening and listening on port 80 or 443 on the Winodws operating system such as Windows Vista, Windows XP, Windows 7, Windows Server 2003 and 2008 and so on.

1. Open Command Prompt window by typing Cmd in Run command box or Start Search, and hit Enter.
2. Type in the following netstat command:

   netstat -o -n -a | findstr 0.0:80

   or

   netstat -o -n -a | findstr 0.0:443

   or simply,

   netstat -aon

   Note: The last command will list all connection that is listening, established, starting, closing and all other states, so the list is long, and user has to manually search for rows that has connection originating or targeting to 1270.0.1:80/443 or 0.0.0.0.80/443.

3. The following line(s) of results should be returned:

   TCP 0.0.0.0:80 0.0.0.0:0 LISTENING 8704

   The last column of each row is the process identified (process ID or PID) which by identified via windows task manager.

   Windows task manager by default did not show the process id, see the figure below how to enable windows task manager to display process id

   

   Identify which process or application is using the port by matching the PID against PID number in Task Manager.

   Identify which process or application is using the port by matching the PID against PID number in Task Manager.