How to check if another program is using the same port as Apache?

There are several ways to check if another program is using the same port as Apache, depending on your operating system. Here are a few examples:

Windows:

Open the Command Prompt by pressing the Windows key + R, then typing "cmd" and pressing Enter.

Type "netstat -a -b" and press Enter. This will show a list of all active network connections and the executables that opened them.

Look for the port that Apache is configured to use (by default, this is port 80 for HTTP and port 443 for HTTPS) in the "Local Address" column. If another program is using the same port, it will be listed here.

MacOS/Linux:

Open a Terminal window.

Type "lsof -i :[port number]" (without the brackets) and press Enter. This will show a list of all processes that have an open internet connection on the specified port.

Look for the port that Apache is configured to use (by default, this is port 80 for HTTP and port 443 for HTTPS). If another program is using the same port, it will be listed here.

You can check apache default listening port in your httpd.conf file, under Listen directive. If the port is being used by another program, you can change the port number for Apache.

Additionally, if you are unable to identify the program that is using the port, you can use specialized software like TCPView for Windows, or lsof on MacOS, Linux