Step 1 : Configuration tab -> Email security > Pop3 Email Proxy > enable the services
Step 2: Mention the Intercept Pop3 port number of your email server default port is 110
Step 3: If the SSL have on your email pop 3 server enable the POP3S
Step 4: This number controls a number of processes required to handle client requests. Depending on the number of clients (LAN Hosts), this number needs to be tuned. The default value is 100.
Step 5: Mention maximum Size for scanning the Virus and spam mail