Microsoft has two "new" Outlooks, one for MacOS and one for Windows. The Windows version will replace Windows Mail & Calendar in late 2024. Microsoft is hoping to eventually replace classic Outlook with new Outlook, but that is years away. It's just not robust and lacks too many features.
While you cannot turn off the option to try the new Outlook in Windows mail, you can turn it off in classic Outlook for Windows.
If you want to disable the option "Try the new Outlook", you need to set this registry key then restart Outlook.
HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Options\General DWORD: HideNewOutlookToggle Value: 1
If you don't want to edit the registry, you can open the Run command using Windows key + R and paste the following into the box.
reg add "HKCU\Software\Microsoft\Office\16.0\Outlook\Options\General" /v HideNewOutlookToggle /t REG_DWORD /d 00000001 /f
If you prefer to use .reg files, I have this ready-to-use registry file available:
HideNewOutlookToggle.reg
If you prefer to download as a compressed folder (.zip):
HideNewOutlookToggle.zip
To switch back to classic Outlook or Windows Mail, you will either have a New Outlook slider on the top right or an option on new Outlook's Help menu.
Slide New Outlook switch to the left to go back to classic Outlook (or windows Mail).
Click Go to classic Outlook (or Windows Mail.)
If you don’t have the slider to turn off the new Outlook or on the Help menu, and can’t find both Outlook's on your Start menu, you need to find Outlook.exe. It's under C:\Program Files (or C:\Program Files (x86)) at \Microsoft Office\root\Office16\OUTLOOK.EXE. Double click to run it then pin it to your Taskbar or Start menu.
If the new Outlook opens when you run outlook.exe, you'll need to edit the registry.
- Open the Registry Editor by typing regedit in the Start menu and open the registry editor when it comes up.
- 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.
If you don't want to edit the registry, you can open the Run command using Windows key + R and paste the following into the box.
reg add "HKCU\Software\Microsoft\Office\16.0\Outlook\Preferences" /v UseNewOutlook /t REG_DWORD /d 00000000 /f
Or, if you prefer, I have a ready to use reg file you can download and run. It is available in both a .reg file and in a .zip file, if you prefer downloading zip files.
UseNewOutlook.reg
Or Zipped:
UseNewOutlook.zip
You can have both Outlooks pinned to the taskbar or start menu and both open at the same time.
Outlook for Mac
To switch between Legacy Outlook and New Outlook, go to the Outlook app menu and choose Legacy Outlook to toggle between versions. (The command weas previously named New Outlook.) You can also switch from the Help menu.
This command should block the new Outlook, hopefully even for updates:
Quit Outlook, open Terminal and paste then run this line:
defaults write com.microsoft.Outlook EnableNewOutlook -Integer 1
Possible values
0 = Switch hidden
1 = Switch displayed, default off
2 = Switch displayed, default on (default)
3 = New Outlook enabled with switch hidden
The above is from Set preferences for Outlook for Mac - Deploy Office | Microsoft Learn
Block New Outlook on Windows 10
Administrators can block new Outlook from being installed as part of the Windows 10 update by adding the following key. (This should work for anyone, but I have not tested it yet to confirm.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsUpdate\Orchestrator\UScheduler_Oobe REG_SZ: BlockedOobeUpdaters Value: ["MS_Outlook"]
If you don't want to edit the registry, open the Command Prompt using Run as Administrator paste the following command. (To open the Command Prompt, type cmd on the start menu or in the search box and choose Run as Administrator.)
reg add "HKLM\SOFTWARE\Microsoft\WindowsUpdate\Orchestrator\UScheduler_Oobe" /v BlockedOobeUpdaters /t REG_SZ /d ["MS_Outlook"] /f
I'm trying to help my dad with this issue. I'm a Mac user who has avoided all Microsoft products for the last two decades just because of nonsense like this. Anyway, my dad noticed the force switch when he clicked on an email link in the body of an email in classic Outlook. It opened New Outlook and presented a page for connecting his accounts to New Outlook. We have not connected anything. I tried to follow your instructions above. First I searched for the toggle switch in New Outlook, but I did not find one - maybe because we haven't activated New Outlook?? so I tried to modify the Registry keys as described above, but his computer does not have the UseNewOutlook key.
Any advice?
If the key does not exist, add it. Or use the reg file I have - https://www.slipstick.com/doit/UseNewOutlook.reg
If new Outlook is open, look on the Help tab - for Go to classic Outlook.
To Anthony Fox, user error. I did not have this issue with her content. You shouldn't try things if you don't understand what you're doing. Be nice...not an "Ahole" as you say...
I have followed your content for years. Just wanted to drop in and thank you for all that you do. Merry Holiday Seasons Greetings to you and yours. Be well and have a prosperous New Year!
I ried this and my computer locked up. I spent the netire day doing a factory reset - thanks Ahole !!
I am trying to switch my Outlook to Classic Outlook and am having no success. My version is the following: Microsoft Outlook Version 1.2024.1204.300 (Production).
Client Version is 20241206007.12.
WebView2 Version is 131.0.2903.99. I went to the web page I was forwarded to after clicking on the button in the help menu the says "Go to Classic Outlook" and I installed it. When I could not find a icon or a listing in the Start menu, I followed your advice and located the Outlook.exe file which was in the location C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE and double clicked on it and when it opened it was version 2016 not 2021 and my activation key would not work. . The new Outlook version is horrible and will not allow me to import my 1000s of old email from Outlook 2003 which I have been using without a problem for decades. How do I get to the correct Classic Outlook 2021?
Did you install 2021 and activate it?
Go to file > Office account and click change license on the right side. sign in using the account the 2021 license is linked to - ifi t is the same as 2016, you'll be asked to choose which license to use.
After the latest Windows update the new version is installed every time after restart of the computer. The regedit keys don´t the job.
I found out the new Outlook version is in the following folder:C:\Program Files\WindowsApps\Microsoft.OutlookForWindows_1.2024.925.0_x64__8wekyb3d8bbwe.
I prevented the installation of the new Outlook bij renaming of the folder Microsoft.OutlookForWindows_1.2024.925.0_x64__8wekyb3d8bbwe.
To do this I had to become owner of the ( Hidden) folder C:\Program Files\WindowsApps.
How to change owner is written here: https://www.guidingtech.com/how-to-access-windowsapps-folder-on-windows/
Are you using Outlook or Windows Mail? Updates definitely will keep trying to switch from Mail, but I have not had an issue with classic Outlook.
Thanks Diane for the keys. I still have the slider and from today also another aditional screen from MS where they say Mail and Agenda becomes Outlook and they invite me to use the new Outlook instead. But thanks to all the registry changes it stops to install Outlook every time.
That second screen refers to the Windows Mail app, not Outlook classic that ships with Office software. The registry keys only apply to Office Outlook.
Do you main the screen is from Mail&agenda?
I might be misunderstanding exactly what you meant by "also another aditional screen from MS where they say Mail and Agenda becomes Outlook" - I thought you meant it was the actual Mail window, but if it's an informational dialog, then its just reminding you that new Outlook is replacing mail. I've seen that dialog come up a few times when using windows mail.
How can I go back to Classic Outlook? I don't like the new outlook at all. I don't see any options on the new outlook to switch back.
Try View tab > View settings > General > About Outlook.