When Pegasus Mail is first installed, you will be ask to set up your Email, over a series of screens as follows:

Screen 1

Your electronic mail account: Your Email Address
Click Next

Screen 2

The address of your POP3 server: yoursite.com
Click Next

Screen 3

Your username and password: email username and password
Click Next

Screen 4

The address of your SMTP server: yoursite.com
Click Next

Screen 5

How do you connect to the Internet? Choose either dialup or network
Click Next
Click Finish

Server Authentication

From the Tools menu, choose Internet options. Under the Sending (SMTP) tab, there is an Authentication section. Check the middle option "Login using my POP3 settings for username and password".

Leaving a Copy on the Server

Under the Receiving (POP3) tab, uncheck "Delete mail from host once successfully retrieved".

Congratulations, you've now setup Pegasus Mail 4 to use your email account. Repeat the above steps to setup further email accounts.