We have users who are just now converting to Win 11 in a shop mostly Win 10. We can share Outlook o365 calendars between Win 10 users. However, when a user upgrades to Win 11, and the Win 10 user sends a shared calendar invite to the Win 11 user, and the Win 11 user selects the ACCEPT button in Outlook, we get the triangle Exclamation mark message, "There was a problem connecting you to the shared calendar. Please ask the person who invited you to send another sharing invitation." We do not know how to fix it. We are an o365 environment all machines are o365.