Port 110 is used by Post Office Protocol v3 (POP3). Email retrieval protocol. Downloads email from server to client. Older than IMAP and sends credentials in plain text on port 110.
What Does an Open Port 110 Mean?
An email server is accepting POP3 connections without encryption. Use POP3S on port 995 instead.
This port should NOT be open to the public internet on typical systems. If you see it open, investigate immediately.
Security Risk Level
High Risk
How to Check if Port 110 Is Open
Use the ExamineIP Port Scanner to check if port 110 is open on any IP address from the public internet. Enter the target IP and select the relevant port preset.
How to Close Port 110
- Stop the service using port 110 if you no longer need it
- Add a firewall rule blocking inbound connections on port 110
- Check your router for port forwarding rules that expose this port
- Run
netstat -ano | findstr :110(Windows) to see which process is using it
Related Ports
POP3 is related to: {implode(‘, ‘, Array)}
Protect Your Open Ports
If you need services like remote access, use a VPN to create a private encrypted tunnel instead of exposing ports directly to the internet. A VPN also hides your real IP address so port scanners cannot identify your device. Try PureVPN or IPVanish.