Your organization uses Microsoft Defender for Office 365. You need to ensure that users are warned before opening potentially malicious attachments in Outlook on the web. Which policy setting should you configure?
This displays a warning before opening a file in a sandboxed view.
Why this answer
The 'Open in protected view' policy setting in Microsoft Defender for Office 365 ensures that when a user opens an email attachment in Outlook on the web, the file is opened in a sandboxed, read-only environment that warns the user of potential risks before allowing full interaction. This directly addresses the requirement to warn users before opening potentially malicious attachments, as it triggers a warning banner and restricts editing capabilities until the user explicitly enables editing.
Exam trap
The trap here is that candidates often confuse 'Dynamic Delivery' with a warning mechanism, but Dynamic Delivery silently replaces the attachment with a safe preview and does not present any user-facing warning before opening.
How to eliminate wrong answers
Option A is wrong because 'Attachments in email are blocked' prevents delivery entirely, which does not warn users before opening—it simply removes the attachment, failing the requirement to provide a warning. Option C is wrong because 'Attachments are held and scanned' refers to the zero-hour auto purge (ZAP) or time-of-click protection that delays delivery for scanning, but it does not present a warning to the user at the point of opening; it either delivers or blocks after scanning. Option D is wrong because 'Dynamic Delivery' delivers a safe, previewed version of the attachment while the original is scanned, but it does not warn the user before opening—it replaces the attachment with a placeholder or preview, not a warning prompt.