[German]I'm pulling out one more topic in this blog post that will concern Windows 10 users in February 2025. Microsoft is pushing the new Outlook app onto systems with the February 2025 security update. At the same time, the Windows Mail and Calendar app will be removed. Let's take a look at the facts.
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The new Outlook app will be shipped
I mentioned in the blog post Windows 10 gets new Outlook app with preview update Jan. 2025 and update Feb. 2025 that the new Outlook app would be distributed at the end of January 2025 and in February 2025.
Microsoft released the cumulative (preview) update for Windows 10 22H2 (KB5050081) on January 28, 2025. This preview update is still optional but, as announced, brings the new Outlook app to the system.
This was already discussed in the German blog post Windows 10/11: Preview Updates Jan. 2025 by German readers in comments. And Microsoft has also documented this in the support article.
After installing the preview update, a new app icon for the new Outlook app will appear in the "Apps" section of the start menu near the classic Outlook. According to Microsoft, there are no changes to the settings or default values.
As preview updates are optional, many Windows 10 users will not have installed this update. But on February 11, 2025, the contents of this preview update will be installed as a regular security update on all Windows 10 22H2 machines.
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Parallel to the rollout to Windows 10 22H2, Microsoft has published the article MC961774 – New deployments of Microsoft 365 desktop client apps to include new Outlook in the Microsoft 365 Message Center. The deployment of new Microsoft 365 desktop client apps will include both classic and new Outlook from the end of February 2025. This change will be available with version 2502. In MC922623, Microsoft describes how administrators can block users from switching to the new Outlook app.
Hands off the Outlook app!
Although Microsoft published this support page with a feature comparison on January 31, 2025, it fails to mention a few things. If you are interested in this new Outlook app, you should read the blog posts Warning: Microsoft Outlook app breaks (company) security and New Outlook app: "Monitoring and surveillance tool for targeted advertising". This is because the new Outlook app requires the login data for all mailboxes and calendars to be sent to Microsoft's servers. These then query the calendars and mailboxes and pull the emails into the Microsoft Cloud. From there, the new Outlook app simply retrieves the content for display.
With regard to the integration of mailboxes in the business sector, I pointed out in my German blog post Neuer Outlook-Client verlangt mindestens Lizenz mit Microsoft 365 Standard what license traps are lurking there. In addition, the new Outlook app has numerous restrictions and many functions are missing. There are then nasty surprises in the business sector (see my German blog post Neue Outlook-App als Problem: Der Ansatz schneidet alle COM-/VBA-Lösungen ab). All this means that the new Outlook app is an absolute no-go.
What can I do?
Microsoft writes in this support article that the new Outlook for Windows will be automatically installed on Windows 10 22H2 with the optional Windows 10 release on January 28, 2025 and with the monthly security update release for Windows 10 on February 11, 2025.
Uninstalling the new Outlook app
As soon as the new Outlook app has been installed on Windows 10, users should be able to uninstall it again. This should be possible via the context menu. Alternatively, there is the option of uninstalling with the following PowerShell instruction:
Remove-AppxProvisionedPackage -AllUsers -Online -PackageName (Get-AppxPackage Microsoft.OutlookForWindows).PackageFullName
Microsoft assures that Windows updates will not reinstall the new Outlook after the one-time removal. As an alternative for the mail and calendar app, users could use Thunderbird as a client, for example.
If you use the Windows Mail and Calendar app and have not yet installed the preview update, you should try to delete the configuration for the email accounts. This is because I assume that Microsoft will take over the configuration from the Windows Mail and Calendar app to be removed when the new Outlook app is installed. However, the access data will then be transferred to the Microsoft Cloud – even if the new Outlook app is subsequently deleted..
Can I block the installation?
Microsoft also writes in this support article that administrators can prevent the installation of the new Outlook app under Windows 10 with the following registry entries – in the key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsUpdate\Orchestrator\UScheduler_Oobe
the REG_SZ value BlockedOobeUpdaters must be entered and set to ["MS_Outlook"]. The support article contains further information on removal under Windows 10 and Windows 11.
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Thanks for the reminder, I've double-checked that we have the registry in place to block the new app. Will report on how successful it is at blocking it once the patch is out.
Can you clarify as its confusing, to me at least, are we talking about the Outlook that's part of Office, or the old Mail app for consumer that ships with Windows?
The old Mail app that is shipped with Windows will disappear after installing the update. It will be replaced by the (new) Outlook app.
This new Outlook app has the same name as the well-known Outlook application from the Office suite, but it's not the same. This new Outlook app is actually a webapplication app that heavily relies on connections with Microsoft servers.
The well-known Outlook application, part of the Office suite, has been renamed Classic Outlook. Microsoft is planning to kill Classic Outlook in a couple of years and force everyone to use this new Outlook app. We'll see if it actually comes to that or not.
Thank you.