Microsoft has too many Outlook apps. There’s a classic Outlook (Win32), then there’s Mail and Calendar (UWP and modern), and now we have Outlook (new), which is a web-based email client. Microsoft wants to replace all the existing Outlook clients with the web app, but it doesn’t want to rush things (for now).

The new Outlook for Windows is in “preview,” but it will soon enter the “general availability” phase, which would be a major milestone in its adoption. At the moment, new Outlook is in the “opt-in” or preview stage, where you have the choice to start using the web app over the full-fledged classic app by enabling the toggle in the top right corner.

Classic Outlook for Windows
This is the opt-in phase, with Classic Outlook for Windows having the toggle to try a new web app | Image Courtesy: WindowsLatest.com

The migration process is split into the following phases: Opt-In, General Availability, Opt-Out, and Cutover (force migration). At this point, no one is being forced to switch yet, with both options available for everyone, but this could change soon.

As Microsoft inches closer to the ‘general availability’ phase, new Outlook will eventually enter “Opt out”.

Outlook web app for Windows
The upcoming opt-out phase with the option to go back to classic Outlook, but this applies to new customers only | Image Courtesy: WindowsLatest.com

In Opt-out, new Outlook will be the default experience for new customers, but you’ll always have the option to switch back to the classic version.

This opt-out phase applies to “new customers” only, those who signed up for Outlook and downloaded the app on Windows. It doesn’t apply to existing customers who will remain on the classic experience until the “cutover” phase.

When I asked for more details, Microsoft support staff clarified that it won’t force people to use the new web-based Outlook anytime soon, and classic Outlook will remain supported until 2029.

However, at some point, classic Outlook may stop receiving new features as the focus shifts to the new Outlook.

Outlook migration plans
Outlook migration plans | Image Courtesy: Microsoft

You can check the above timeline diagram to understand the tech giant’s plans better, or you can just read my simple explanation of the next two big milestones:

  • Opt-Out: At some point after general availability (GA), you can choose to stop using the new Outlook if they don’t like it. But again, Microsoft will give everyone a 12-month heads-up before they have to switch for good.
  • Cutover: Eventually, Microsoft will move everyone to the new Outlook whether you like it or not. This doesn’t mean the old version won’t be available anymore, as you can always switch back. But even at this stage, Microsoft will have given users at least 12 months’ notice to get used to the idea.

Microsoft’s approach is quite straightforward: they promise to inform everyone about every big change at least 12 months before the implementation.

Classic Outlook is here to stay, but you’ll need to switch at some point

I expect the new Outlook experience to enter the final “cutover” phase in 2025 or 2026, when everyone will be moved to the web version with the option to return to the Win32 client.

However, this doesn’t mean classic Outlook for Windows will stop working, as it will remain supported until at least 2029.

It’s pretty obvious that the tech giant doesn’t want to rush things. Anyone who uses Outlook regularly is aware of the fact the web app is a major downgrade from the classic Outlook and even the Mail and Calendar app.

Outlook web app hated by everyone
The majority hates the new Outlook experience | Image Courtesy: WindowsLatest.com

On X, I asked our readers if they liked the new Outlook (web app) for Windows, and most of them (read 90%) hated the new experience.

About The Author

Mayank Parmar

Mayank Parmar is an entrepreneur who founded Windows Latest. He is the Editor-in-Chief and has written on various topics in his seven years of career, but he is mostly known for his well-researched work on Microsoft's Windows. His articles and research works have been referred to by CNN, Business Insiders, Forbes, Fortune, CBS Interactive, Microsoft and many others over the years.