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Classic Outlook is NOT Going Away in 2026

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› Outlook › Classic Outlook is NOT Going Away in 2026

Last reviewed on March 6, 2025     8 Comments

Applies to: Outlook (classic), Outlook (new)

A user asked about an article he saw in an online tech magazine, where the article said “classic Outlook is scheduled to go out of service by the end of April 2026.”

The user went on to add “I don’t think I’ll ever be ready to ditch Outlook, especially for an on-line version! “

First, classic Outlook is going to be with us and supported, with at least security updates, until 2029, if not longer. I’m hoping longer... I need VBA and PowerShell support. (When they remove classic Outlook from the subscription, I'll switch to a perpetual version.)

Microsoft really wants to push users into new Outlook (even though right now, the haters outnumber the people who like it) so they are changing from opt-in (you decide if you want to try new Outlook) to opt-out, where Microsoft switches you to new Outlook and you decide if you want to switch back.

Secondly, while I am not a fan of new Outlook, especially for users who do not use outlook.com or Microsoft 365 business mailboxes, new Outlook is not “an online version”. It is a desktop app that uses the same scripts as Outlook on the web, but with a current maximum of 180 days of mail cached locally if you are disconnected from the internet. (Offline options are in View tab > View Settings > General > Offline. Settings are per-account.)

In 2025 for Business Standard and in 2026 for Enterprise licenses, Microsoft will be switching new Outlook on for users. They will still be able to switch back to classic. Prior to being switched to new Outlook, users will receive warnings via in-app notifications.

From the Microsoft article Switch to new Outlook for Windows it is explained like this:

Small and Medium Businesses
Starting January 2025 and over the following months, if you are a classic Outlook user on the Current Channel with a Business plan, you will automatically be switched to the new Outlook after receiving a series of in-app notifications. You can choose to switch back to classic Outlook at any time, using the toggle in new Outlook. Both users and IT Admins can also turn off the automatic switch if not ready to try the new Outlook.

Users will not be switched to new Outlook if one or more of the following is true:

  1. New Outlook toggle is hidden via policy
  2. Perpetual license is in use
  3. If using an account not supported in new Outlook (only an on-prem Exchange mailbox currently)
  4. Admin set a policy blocking it

To hide the new Outlook toggle (item 1): See Use Classic Outlook, not New Outlook for the registry key you need to set. (I have a ready-to-use reg file available in the article.)

Information on the policy to block the switch (item 4) is in this article: Control the installation and use of new Outlook

You can use both classic Outlook and new Outlook, including at the same time. (I often have both open.) Switch on Try new Outlook, set up the accounts and pin new Outlook to the taskbar. Then toggle off New Outlook and restart classic Outlook. If the toggle is missing in the upper right of the app, look on the Help tab for the “Go to classic Outlook” button.

Because the icons are both blue with a white O, you probably won't want them to be side-by-side on the taskbar. (Classic Outlook is on the left, new Outlook on the right.)
classic and new Outlook icons

Who should not switch to new Outlook?

Anyone using COM add-ins or VBA (or PowerShell) to extend or automate classic Outlook. Anyone using custom views or client-side rules.

For POP and IMAP accounts, my main issue is that the new Outlook pulls your mail into the Microsoft Cloud then syncs it to new Outlook rather than connecting the app directly to the mailbox. Offline caching is limited to up to 180 days of messages.

The "Microsoft Cloud" is what allows it to sync calendar and contacts from Gmail, Yahoo, and iCloud. If you use those accounts and want the calendar and contacts to sync, definitely try new Outlook. (The Outlook mobile apps work the same way - syncing your mailbox to the Microsoft cloud, which syncs with the app.)

Tip: When you remove an account from new Outlook and are asked if you want to remove it from all devices, selecting Yes will delete the mailbox from the cloud server. If you are using new Outlook on other computers or the Outlook mobile app, the account won't be automatically deleted from the devices but will stop syncing. You need to remove the account from the other devices manually.

Message Center articles for admins

Microsoft published articles for administrators in the message center:

For admins with Business Standard in the tenant: Toggle to new Outlook

Summary
Starting January 6, 2025, Microsoft 365 Business Standard and Premium users will be switched from classic to new Outlook for Windows. Users can revert to classic Outlook and provide feedback. The rollout requires no admin action but can be managed through a new policy.

Tenants with Enterprise subscriptions will have a message at Toggle to new Outlook

Summary
Starting April 2026, Microsoft 365 for Enterprise users will be switched from classic to new Outlook for Windows, with the option to revert back. This change aims to enhance user experience with modern features. Organizations are notified to prepare, with automatic rollout requiring no admin action but allowing opt-out options.

Classic Outlook is NOT Going Away in 2026 was last modified: March 6th, 2025 by Diane Poremsky

Related Posts:

  • Use Classic Outlook, not New Outlook
  • Classic Outlook Missing from Computers
  • Outlook.com and Modern Authentication Questions
  • Opening PST files in New Outlook

About Diane Poremsky

A Microsoft Outlook Most Valuable Professional (MVP) since 1999, Diane is the author of several books, including Outlook 2013 Absolute Beginners Book. She also created video training CDs and online training classes for Microsoft Outlook. You can find her helping people online in Outlook Forums as well as in the Microsoft Answers and TechNet forums.

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Jack Sajad (@guest_221633)
February 25, 2025 1:21 pm
#221633

Diane, Hope you are having a wonderful day. I read your various posting here about new outlook and classic old outlook. I need your HELP please give me step by step instructions how to restore old classic outlook so I can use my hosted emails at exchange server provided by Intermedia and disable or get rid of new outlook. I dont want to use cloud microsoft email if I can avoid that I would like to keep my emails local and under my control. On Feb 23rd 2025 I renewed my msoffice 365 subscription and hell went lose on me I lost the complete outlook and my emails setup from my computer and since than I am trying tor restore the classic old outlook we cannot find it anywhere in control panel and there is no option to toggle between the new and old outlook even in new outlook app. I read that it is hidden and tricky to find it to toggle it back to classic old outlook PLEASE HELP ME to get this restored. I took screen shots photos of my control panel / startup and app section but there is no sign of classic outlook. Please guide… Read more »

SCREEN-SHOT-IN-APP-ON-MY-COMP-DOES-NOT-SHOW-CLASSIC-OR-JUST-OULOOK
THIS-IS-STARTUP-SCREEN-SHOT-ONLY-SHOWS-NEW-OUTLOOK-AND-NO-SIGN-OF-CLASSIC-OUTLOOK
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Diane Poremsky(@diane-poremsky)
Author
Reply to  Jack Sajad
February 25, 2025 4:16 pm
#221634

Is Outlook.exe here - "C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE" (assuming you have 64 bit office installed)

If not, you need to install it from https://support.microsoft.com/office/you-can-t-open-classic-outlook-on-a-new-windows-pc-5c94902b-31a5-4274-abb0-b07f4661edf5 - I recommend the download version, not the store version.

To get rid of new Outlook - if the toggle is not on the Help tab, see https://www.slipstick.com/outlook/classic-outlook-not-new-outlook/ - the value at the top will hide the try Outlook switch in classic Outlook and block Microsoft from trying to switch it back.

To enable classic (if clicking the Outlook icon opens new outlook): (also at my link above)
>>>
Go to Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Preferences.
Find UseNewOutlook and double click on it.
Set the Value Data field to 0.
>>>

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Jann (@guest_221630)
February 22, 2025 6:45 am
#221630

Have to laugh when people talk about Russia and China wanting to inspect and control their residents' lives - 'free world' US quasi-monopolies such as Microsoft, Meta, Google etc. are the worst offenders IMHO, and all of this has been allowed way before the recent change of US government. If I read the article correctly, Microsoft wants to try and prevent users from keeping their data private on their local computer, and instead force them into 'sharing' their data with Microsoft (and heaven knows who else) in the Cloud (i.e. on Microsoft servers)? "with a current maximum of 180 days of mail cached locally if you are disconnected from the internet" At present I can search my own and my clients Outlook data of the past 20 years. Fast. Locally. Without an internet connection (should I prefer). And without Microsoft and their AI department being able to snoop. I would be interested to hear of any possible valid reason for Microsoft making this change, as the most obvious reason IMHO is that the company does indeed want to snoop and/or use for AI purposes.... (and, should someone point to some vague privacy promise in the small print, I think we… Read more »

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Diane Poremsky(@diane-poremsky)
Author
Reply to  Jann
February 23, 2025 10:16 am
#221631

>> Microsoft wants to try and prevent users from keeping their data private on their local computer, and instead force them into 'sharing' their data with Microsoft (and heaven knows who else) in the Cloud (i.e. on Microsoft servers)? >> This is essentially correct. They arent preventing you from keeping it local but if you want to use new Outlook, you need to store in the Microsoft cloud. I trust them as far as not snooping or using the data but I don't like the 'middle man' aspect of it. As an enviromentalist at heart who lived a hour or so from Three Mile Island when it blew (I know, did not exactly blow up. :)), I am concerned about the effects of ever-larger data centers and their need for more electricy and the harm it does to the enviroment. (Not to mention, driving up costs for households and other businesses.) There will come a point in time when storing everything in the cloud is not substainable or cost effective and Microsoft may either set limitations or add fees or both. For the enviromental reasons alone, I prefer a mail app that directly connects to my server for non-microsoft accounts.… Read more »

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Diane Poremsky(@diane-poremsky)
Author
Reply to  Jann
February 23, 2025 11:09 am
#221632

BTW -
>>
I would be interested to hear of any possible valid reason for Microsoft making this change,
>>

They want to use one set of React scripts to power Outlook on the web and the app. This cuts down on the number of developers they need. This is not a problem for Microsoft accounts as everything is on the server and users have the same interface reguardless of which method they use. The issue is connecting to IMAP / POP accounts... and by doing the syncing at the server they can update the code faster and not worry if users installed the updates.

By doing it this way, they share one cloud mailbox with all your devices - Outlook mobile uses the same mailbox (but not the same react scripts). Actially... that is where they started on this plan. Acompli used this method (with AWS servers storing the data) then Microsoft bought them out and developed Outlook mobile.

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Bernice (@guest_221596)
January 26, 2025 5:43 am
#221596

Hi Diane,
meine Frage ist folgende: Die letzte Sitzung/Konferenz vom 16.01. bei Teams war nicht wiederzufinden im Verlauf! Beim öffnen von Teams begann es mit den Konferenzen im Sept. 2024. Von dort ging es nur zurück Juli Juni, etc.pp. Aber keine Konferenzen von Nov., Dez. 24 usw. Wie kann das sein?
2 Frage: ist es möglich wieder die classische Version zu nutzen oder zumindest einen Zugang zu haben?
Viele Grüße
Bernice

>>
my question is the following: The last meeting/conference on 16.01. at Teams could not be found again in the course! When opening Teams, it started with the conferences in Sept. 2024. From there it only went back July, June, etc.pp. But no conferences from Nov., Dec. 24 etc. How can that be?
2 Question: Is it possible to use the classic version again or at least have an access?
>>

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Diane Poremsky(@diane-poremsky)
Author
Reply to  Bernice
February 26, 2025 8:03 am
#221635

On 2: Classic Teams, no not if using Microsoft 365. Some specilized tenants, such as government or defense might still have it (until June 2025) but regular folks will not. Sorry.

Classic Outlook, yes, that is still available.

As for why the meetings are missing: archiving or policies would be the best guess as to why they are missing. The Microsoft 365 Admin might know what happened.

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Jess (@guest_221584)
January 22, 2025 8:37 am
#221584

Thank you for the concise, informative, pertinent and timely article. There is hope for the Internet.

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