If your specific email client program is not listed, you can set up any other email client by using the following instructions:

• In your email client create a new 'account'
• For the incoming and outgoing server name/address use the numeric IP address of the VPOP3 computer
• For the username/account name/login, use the user name defined in the Users → Accounts page in the VPOP3 settings
• For the password, use the password defined for the above user, in the Users → Accounts page in the VPOP3 settings

That's it