VSE 8.x only supports Messaging Application Programming Interface (MAPI) in Microsoft Exchange connected environments that run Microsoft Outlook as the mail client.

VirusScan does not support Internet Message Access Protocol (IMAP) or Post Office Protocol 3 (POP3) mail.

Email Scanning can become redundant depending on your email environment. The on-access scanner in VSE scans attachments when it runs or writes to local disk. It happens after Outlook Scan finishes scanning.