Users and administrators report that on some systems with Microsoft 365, the Outlook app preview is suddenly installed by Microsoft without the user's approval.
In patchmanagement an administrator reports:
I'm seeing issues on 4 devices so far where, after Tuesday, the Windows Mail app has now been renamed to “Outlook Pre” (I assume it means preview) and replaced the Outlook 365 icons and shortcuts. Opening it (Outlook Pre) causes disabling Outlook from MS 365;
Using the control panel to try to repair Microsoft 365 (because I have Outlook again) resulted in a complete removal of Microsoft 365. Reinstalling Microsoft 365 from office.com was the only way to get it working again.
So the Outlook application was replaced without asking the final one user. The only way to bring back the old Outlook is to reinstall it from office.com.
Another user on the Microsoft forum warns by posting on Reverting new Outlook 365
And another one in the post “New” Outlook for Windows UWP App (Preview) Installed Without Permission.
I hovered my mouse over that toggle switch to try to find further information about its purpose but I am certain that I never turned that switch on, and the next day I was appalled to discover that this preview of the MS Outlook for Windows UWP app v1.2023.425.600 had been installed on my system without my permission.
So be careful if useste Microsoft 365. If any of the above has happened to you, let us know in the comments of this post.
