Disable New Outlook Toggle via PowerShell

Overview

This PowerShell script disables the "New Outlook" toggle for all eligible user profiles on a Windows machine. It modifies the Windows registry settings for Microsoft Outlook to enforce this change.

How It Works

1. Retrieves all user SIDs from the HKEY_USERS registry.
2. Skips system and service accounts.
3. Checks if the Outlook registry path exists for each user.
4. Sets the registry values to:
   • UseNewOutlook = 0 in Preferences
   • HideNewOutlookToggle = 1 in Options\General
5. Displays a summary of the changes made.

Registry Paths Affected

• HKEY_USERS\<User SID>\Software\Microsoft\Office\16.0\Outlook\Preferences
  • UseNewOutlook (DWORD) = 0
• HKEY_USERS\<User SID>\Software\Microsoft\Office\16.0\Outlook\Options\General
  • HideNewOutlookToggle (DWORD) = 1

Usage

Run the script as an administrator:

powershell -ExecutionPolicy Bypass -File DisableNewOutlook.ps1

Requirements

• Administrator privileges.
• Windows machine with Microsoft Office 2016 (16.0) or later installed.
• PowerShell 5.1 or later.

Notes

• If the registry paths do not exist, the script will notify you but will not create them.
• Only user profiles with Outlook registry settings present will be modified.

License

This script is provided as-is without any warranty. Use at your own risk.

Author

DaanSelen