Many connectivity problems with websites, game servers, or email are caused by blocked or misconfigured ports and firewall rules. This guide explains the most common issues and how to resolve them.

What Are Ports?

Ports are like “channels” that allow different services to communicate over the internet.

  • Example: Web traffic uses port 80 (HTTP) and 443 (HTTPS).
  • Game servers and apps use their own unique ports.

If a port is blocked by a firewall, the service may not be accessible.

Common Hosting Ports

Service Default Port(s)
HTTP (Websites) 80
HTTPS (SSL Websites) 443
FTP 21
SFTP (SSH File Access) 22
MySQL Database 3306
Email - SMTP (Outgoing) 25, 465, 587
Email - IMAP (Incoming) 143, 993
Game Servers - Minecraft 25565
Game Servers - FiveM 30120
Game Servers - FiveM - txAdmin 40120

Common Issues

  • Website not loading → Ports 80/443 may be blocked or DNS not configured.
  • FTP/SFTP not connecting → Ensure you’re using the correct port (FTP = 21, SFTP/SSH = 22).
  • Email not sending → Port 25 may be blocked by your ISP; use 465 or 587 instead.
  • Game server not showing up → The required game port may not be open or correctly forwarded.
  • Database errors → External connections to port 3306 may be blocked by default (usually only accessible locally).

How to Fix Firewall/Port Problems

  1. Check Allowed Ports
    • Log in to your control panel or server firewall settings.
    • Make sure the required ports are open.
  2. Use Alternative Ports (If ISP Blocks)
    • Some ISPs block port 25 (SMTP). Switch to 587 or 465 for outgoing mail.
  3. Port Forwarding (Game Servers)
    • If running a server at home, configure your router to forward the correct ports.
    • On hosted servers, confirm that the required ports are allocated and open.
  4. Testing Ports

Troubleshooting Tips

  • Some ports may be restricted for security reasons (e.g., external MySQL access).
  • Firewalls may block connections during DDoS mitigation or high traffic.
  • If email clients won’t connect, try switching between IMAP ports (143/993).