This policy setting allows you to configure e-mail scanning. When e-mail scanning is enabled, the engine will parse the mailbox and mail files, according to their specific format, in order to analyze the mail bodies and attachments. Several e-mail formats are currently supported, for example: pst (Outlook), dbx, mbx, mime (Outlook Express), binhex (Mac). If you enable this setting, e-mail scanning will be enabled. If you disable or do not configure this setting, e-mail scanning will be disabled.
Solution
Policy Path: Windows Components\Windows Defender Antivirus\Scan Policy Setting Name: Turn on e-mail scanning