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← Back to Microsoft Office 365 ProPlus Security Technical Implementation Guide

V-223343

CAT II (Medium)

File attachments from Outlook must be opened in Excel in Protected mode.

Rule ID

SV-223343r961092_rule

STIG

Microsoft Office 365 ProPlus Security Technical Implementation Guide

Version

V3R5

CCIs

CCI-001170

Discussion

This policy setting allows you to determine if Excel files in Outlook attachments open in Protected View. If you enable this policy setting, Outlook attachments do not open in Protected View. If you disable or do not configure this policy setting, Outlook attachments open in Protected View.

Check Content

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Excel 2016 >> Excel Options >> Security >> Trust Center >> Protected View >> Turn off Protected View for attachments opened from Outlook is set to "Disabled".

Use the Windows Registry Editor to navigate to the following key: 

HKCU\software\policies\microsoft\office\16.0\excel\security\protectedview

If the value DisableAttachmentsInPV is REG_DWORD = 0, this is not a finding.

Fix Text

Set policy value for User Configuration >> Administrative Templates >> Microsoft Excel 2016 >> Excel Options >> Security >> Trust Center >> Protected View >> Turn off Protected View for attachments opened from Outlook to "Disabled".