Usually, the port used for the Incoming Mail Server/POP is 110, Outgoing Mail Server/SMTP Service is 25. However, there might be a situation where your ISP might be blocking the use of these ports, especially SMTP port 25, many ISPs block port 25 in order to minimize the amount of spam sent using their network.
If you are facing issues sending or recieving mails using the default ports, you can confirm with your ISP whether the standard ports are indeed blocked by them.
To circumvent this, you can use the alternate ports shown below.
- Port 110 - this is the default POP3 non-encrypted port
- Port 995 - this is the port you need to use if you want to connect using POP3 securely
- Port 143 - this is the default IMAP non-encrypted port
- Port 993 - this is the port you need to use if you want to connect using IMAP securely
- Port 25 - this is the default SMTP non-encrypted port
- Port 465 - this is the port used, if you want to send messages using SMTP securely
