Outlook Rich Text options: registry value message rtf formatUserHKCU\software\policies\microsoft\office\16.0\outlook\options\mail

Policy ID: L_OutlookRichTextoptions
Scope: User Configuration
Supported on: At least Windows Server 2008 R2 or Windows 7
Source: Microsoft 365 Apps / Office Administrative Templates (version 5568.1000)
Category: Microsoft Outlook 2016 › Outlook Options › Mail Format › Internet Formatting

Registry

message rtf format

REG_DWORDUser

HKCU\software\policies\microsoft\office\16.0\outlook\options\mail Current key

Enabled value: Depends on the option value
Element: Use this format:

Options
Item	Stored value
Convert to Plain Text format	1

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\outlook\options\mail]

; Options (use only one)
; Convert to Plain Text format
"message rtf format"=dword:00000001

CMD

:: Options (use only one)

:: Convert to Plain Text format
reg add "HKCU\software\policies\microsoft\office\16.0\outlook\options\mail" /v "message rtf format" /t REG_DWORD /d 1 /f

PowerShell

# Common: create the key
New-Item -Path 'HKCU:\software\policies\microsoft\office\16.0\outlook\options\mail' -Force | Out-Null

# Options (use only one)
# Convert to Plain Text format
New-ItemProperty -Path 'HKCU:\software\policies\microsoft\office\16.0\outlook\options\mail' -Name 'message rtf format' -PropertyType DWord -Value 1 -Force | Out-Null