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← Back to Microsoft Outlook 2016 Security Technical Implementation Guide

V-251867

CAT II (Medium)

Outlook Rich Text options must be set for converting to plain text format.

Rule ID

SV-251867r961863_rule

STIG

Microsoft Outlook 2016 Security Technical Implementation Guide

Version

V2R4

CCIs

CCI-000366

Discussion

Outlook automatically converts Rich Text Format (RTF) messages that are sent over the internet to HTML format, so that the message formatting is maintained and attachments are received. This setting controls how Outlook sends RTF messages to internet recipients.

Check Content

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Outlook Options >> Mail Format >> Internet Formatting "Outlook Rich Text options" is "Enabled: Convert to Plain Text format".

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

HKCU\Software\Policies\Microsoft\Office\16.0\outlook\options\mail

Criteria: If the value Message RTF Format is REG_DWORD = 1, this is not a finding.

Fix Text

Set the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Outlook Options >> Mail Format >> Internet Formatting "Outlook Rich Text options" to "Enabled: Convert to Plain Text format".