Fix "Port 80 Already in Use"

Find the Conflicting Process

sudo lsof -i :80
sudo netstat -tlnp | grep :80
sudo ss -tlnp | grep :80

Common Conflicts

1. Nginx vs Apache

# If using Apache, stop Nginx
sudo systemctl stop nginx
sudo systemctl disable nginx

# If using Nginx, stop Apache
sudo systemctl stop apache2
sudo systemctl disable apache2

2. Docker Container

docker ps
docker stop container_name
docker rm container_name

3. Skype (Windows/Linux)

Skype uses port 80/443 by default. Change Skype settings to disable port 80 usage.

4. Node.js App

sudo pkill node
# Or find and kill specific
sudo kill -9 $(sudo lsof -t -i:80)

Force Kill Process by Port

sudo fuser -k 80/tcp
sudo fuser -k 443/tcp

Change Your Web Server Port

# Nginx - change listen 80 to listen 8080
# Apache - change Listen 80 to Listen 8080

Check for Zombie Processes

ps aux | grep defunct
sudo reboot

After clearing the port, restart your web server.