Microsoft will update the behavior for switching between new and classic Outlook for Windows. Starting mid-May 2025, new Outlook will stay minimized when switching back to classic Outlook. From early June 2025, users can open classic Outlook without leaving new Outlook. This change requires no admin action and will be automatic.
Applies to: Exchange Online · Microsoft 365 apps
Source: mc.merill.net — data via Merill Fernando's open archive (MIT).