Using Classic Outlook on Windows for personal email, calendar, and contact management
Just for awareness the OWA Team is working on a fix for this issue. I don't have an ETA yet but it is being worked on with priority. The last update is the fix is in code review so hopefully release soon.
I have one user at a client experiencing this issue. The only difference here is that Outlook is launching the browser on application start every time. No user interaction besides clicking the Outlook shortcut to launch.
We are running the latest stable release, and OWA is disabled in M365.
It launches this link https://outlook.office.com/opx/******@clientname.com/activityfeed/?hostApp=outlookdesktop&culture=en-US Hope this fix gets released soon!
This seems completely related: https://answers.microsoft.com/en-us/outlook_com/forum/all/is-anybody-getting-this-internet-popup-when-using/ad56f56b-cbd3-43bb-8f5f-64b8eb0b896f