Control installing and using new Outlook

This article provides guidance for administrators who want to control the installation of the new Outlook in an organization and how users access and use the app.

Prevent users from switching to new Outlook

Some administrators might choose to hide the Try the new Outlook toggle from appearing in the classic Outlook for Windows until the organization is ready to migrate the Outlook app.

Hiding the "new Outlook" toggle is available as a cloud policy in the Microsoft 365 Apps admin center. To set up the policy:

1. Sign in to the Microsoft 365 Apps admin center.
2. Under Customization, select Policy Management.
3. Select Create.
4. Search for the Hide the "Try the new Outlook" toggle in Outlook policy, and then enable it.

Alternatively, you can use the following Windows registry key to hide the Try the new Outlook toggle:

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Options\General]
"HideNewOutlookToggle"=dword:00000000

To later enable the policy, set the registry key to 1:

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Options\General]
"HideNewOutlookToggle"=dword:00000001

For more information about this process, see the Use the registry to enable or disable the "Try the new Outlook" toggle in classic Outlook section of "Enable or disable user access to Outlook for Windows in Exchange Online."

Block new Outlook preinstallation on Windows

Windows 11

Windows 11 builds later than 23H2 have the new Outlook app preinstalled for all users. Currently, there isn't a way to block the new Outlook from being installed in these builds. If you prefer not to have new Outlook show up on your organization's devices, you can remove it after it's installed during the update.

To remove the app package, run the Remove-AppxProvisionedPackage cmdlet by using the PackageName parameter value, Microsoft.OutlookForWindows. After the package is removed, Windows updates won't reinstall new Outlook.

Run the following command in Windows PowerShell:

Remove-AppxProvisionedPackage -AllUsers -Online -PackageName (Get-AppxPackage Microsoft.OutlookForWindows).PackageFullName

Additionally, remove the following Windows orchestrator registry value:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsUpdate\Orchestrator\UScheduler_Oobe\OutlookUpdate

For any device that installed the March 2024 Non-Security Preview release (or later cumulative update) for Windows 11, version 23H2, Windows Orchestrator respects the deprovisioning cmdlet. Therefore, it's not necessary to remove this registry value in this case.

Windows 10

The new Outlook app is automatically installed on Windows 10 devices as part of the following updates:

• The optional Windows 10 release on January 28, 2025
• The monthly security update release for Windows 10 on February 11, 2025

To prevent the installation of new Outlook on your organization's devices, add the following registry value:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsUpdate\Orchestrator\UScheduler_Oobe

Then, add a REG_SZ registry setting that's named BlockedOobeUpdaters, and give it a value of ["MS_Outlook"].

To remove the app package after it's installed, run the Remove-AppxProvisionedPackage cmdlet by using the PackageName parameter value, Microsoft.OutlookForWindows.

Run the following command in Windows PowerShell:

Remove-AppxProvisionedPackage -AllUsers -Online -PackageName (Get-AppxPackage Microsoft.OutlookForWindows).PackageFullName

After the package is removed, Windows updates won't reinstall new Outlook.

User installations

In cases of user installations (for example, if users use the toggle to install the new Outlook for Windows), run Remove-AppxPackage. The AppxPackage cmdlets are used to manage applications for current users, and AppxProvisionedPackage cmdlets are used to manage default applications for both current and future users of the system.

Run the following Windows PowerShell command to remove the new Outlook for Windows for all users:

Remove-AppxPackage -AllUsers -Package (Get-AppxPackage Microsoft.OutlookForWindows).PackageFullName

Block new Outlook installation as part of Mail and Calendar deprecation

Users can switch to new Outlook from the Mail and Calendar apps that are included in Windows. Support for Windows Mail and Calendar ended on December 31, 2024. We're automatically switching active users to the new Outlook app.

If you want to block users from getting the new Outlook from Windows Mail and Calendar applications, you can uninstall these apps from the user's devices.

To uninstall the apps, follow the instructions in Remove-AppxProvisionedPackage to remove the app package by using the PackageName parameter that has the value, microsoft.windowscommunicationsapps.

Run the following Windows PowerShell command:

Get-AppxProvisionedPackage -Online | Where {$_.DisplayName -match "microsoft.windowscommunicationsapps"} | Remove-AppxProvisionedPackage -Online -PackageName {$_.PackageName}

To remove the Mail and Calendar apps for current users, run the following Remove-AppxPackage command in Windows PowerShell:

Remove-AppxPackage -AllUsers -Package (Get-AppxPackage microsoft.windowscommunicationsapps).PackageFullName

Alternatively, you can remove the apps through Intune or by following the instructions in Uninstall applications with Configuration Manager.

Prevent users from acquiring new Outlook from Microsoft Store

The new Outlook for Windows app is also available in the Microsoft Store. To prevent users from downloading the app from the store, you can block store access by following the instructions in Configure access to the Microsoft Store app.

Opt out of new Outlook migration

Starting in January 2025, users who have Microsoft 365 Business Standard and Premium licenses are being automatically migrated from the classic Outlook for Windows to new Outlook for Windows. Users receive in-app notifications before the migration. They can opt out of the automatic migration through Outlook Options > General. Users who are switched to the new Outlook can toggle back to the classic Outlook if they want.

For more information, see: Switch to new Outlook for Windows.

Admin control over migration

Admins can disable the user setting for automatic migration to prevent users from being switched to the new Outlook.

Policy: Manage user setting for new Outlook automatic migration

The policy can be configured by using the following values:

• Not set (Default): If you don’t configure this policy, the user setting for automatic migration remains uncontrolled, and users can manage it themselves. By default, this setting is enabled.
• 1 (Enable): If you enable this policy, the user setting for automatic migration is enforced. Automatic migration to the new Outlook is allowed, and users can't change the setting.
• 0 (Disable): If you disable this policy, the user setting for automatic migration is turned off. Automatic migration to the new Outlook is blocked, and users can't change the setting.

Configuring the policy using the Windows registry

To disable automatic migration:

[HKEY_CURRENT_USER\Software\Policies\Microsoft\office\16.0\outlook\preferences]
"NewOutlookMigrationUserSetting"=dword:00000000

To enable automatic migration:

[HKEY_CURRENT_USER\Software\Policies\Microsoft\office\16.0\outlook\preferences]
"NewOutlookMigrationUserSetting"=dword:00000001

Setting in Group Policy

You can download the latest Group Policy Administrative Template file from the Microsoft Download Center.

Setting in Cloud Policy

You can also set this policy through the Cloud Policy service from the Microsoft 365 Apps admin center. For more information about Cloud Policy, see Overview of Cloud Policy service for Microsoft 365.

Manage automatic setup of classic Outlook accounts and settings in new Outlook 

We're providing updates to make sure that users get the most familiar experience possible when they try new Outlook. This process includes keeping the accounts and settings that users have in classic Outlook.  

Starting in August 2025, accounts and settings are being automatically set up in new Outlook in the background for classic Outlook users who meet the following criteria: 

• The new Outlook is installed on their device.

• The "new Outlook" toggle is visible in classic Outlook (that is, it's not hidden by the administrator by using this policy).

Notice that this process doesn't automatically start new Outlook for the users. However, it makes sure that if users choose to start new Outlook directly (without toggling from classic Outlook), they still have their classic Outlook accounts and settings. 

Users receive an in-app notification before the automatic setup is finished. Also, they can opt out of the experience through Outlook Options > General > New Outlook. 

Admin control over automatic setup

Administrators can disable the user setting for automatic setup of classic Outlook to prevent classic Outlook accounts and settings being set up in new Outlook in the background.

Policy: Manage automatic setup of classic Outlook accounts in new Outlook

The policy can be configured by using the following values:

• Not set (Default): If you don't configure this policy setting, the user setting for automatic setup of user accounts and settings remains uncontrolled, and users can manage it themselves. By default, this setting is enabled. 

• 1 (Enable): If you enable the policy, the user setting for automatic setup of user accounts and settings in new Outlook is enforced. Automatic setup in new Outlook is allowed, and users can't change the setting. 

• 0 (Disable): If you disable the policy, the user setting for automatic setup of user accounts and settings in new Outlook is turned off. Automatic setup in new Outlook is blocked, and users can't change the setting. 

Configuring the policy using the Windows registry

To disable automatic account and settings setup in new Outlook:

[HKEY_CURRENT_USER\Software\Policies\Microsoft\office\16.0\outlook\preferences] 
"NewOutlookAutomaticSetupUserSetting "=dword:00000000

To enable the automatic account and settings setup in new Outlook:

[HKEY_CURRENT_USER\Software\Policies\Microsoft\office\16.0\outlook\preferences] 
"NewOutlookAutomaticSetupUserSetting "=dword:00000001

Setting in Group Policy

You can download the latest Group Policy Administrative Template file from the Microsoft Download Center.

Setting in Cloud Policy

You can also set this policy through the Cloud Policy service from the Microsoft 365 Apps admin center. For more information about Cloud Policy, see Overview of Cloud Policy service for Microsoft 365.

Conditional access to the new Outlook App

Many organizations have common access concerns that Conditional Access policies can help resolve. For example:

• Requiring multifactor authentication for users
• Blocking or granting access from specific locations
• Blocking risky sign-in behaviors
• Requiring organization-managed devices to be used

A more granular control can be offered by using OWA Mailbox Policies together with the ConditionalAccessPolicy parameter. For example, when users are on noncompliant devices, OWA mailbox policies limit their capabilities. For example, restricting attachments.

To learn more about Conditional Access and how to configure it, follow the instructions in Require compliant, hybrid joined devices, or MFA to grant or block access. To configure OWA Mailbox Policies, check OWA Mailbox Policy - Conditional Access Policy.

Block mailbox access on new Outlook

Users might acquire the new Outlook app through various flows, as outlined in the previous sections. To prevent mailbox access from the new Outlook, regardless of how users acquire it, use an Exchange mailbox policy to block organization (work or school) mailboxes from being added to the app. This policy serves as the final block, making sure that users can't use their work or school accounts even if they have the app on their device.

Mailbox policies are applied to the work or school email account and not at the device or app level. Therefore, to prevent users from using the app together with other accounts that aren't their work or school email account, we recommend that you block access to the app (as discussed in previous sections).

To manage mailbox access, follow the instructions in Enable or disable user access to Outlook for Windows in Exchange Online.