This problem has completely shot my entire day. I reformatted my old windows XP comp and tried installing XAMPP only to find that when i try to start Apache xampp claims por
Only one process can use port 80 at a time. Port 80 is the default port for web servers, so when you navigate to websites over HTTP, you are actually navigating to that server's port 80 by default (when you use HTTPS, the port is 443).
You can try to hunt down all the programs that are running on port 80, but there's an easier way that will work for development. When running XAMPP, click "Config" under "Apache". Replace Listen 80 with Listen 8080 and ServerName localhost:80 to ServerName localhost:8080.
Then, when you want to look at your masterpiece, navigate to http://localhost:8080 in your browser.