![(Updated) Auto upgrade of shared calendars from legacy MAPI model to modern REST model [MC1287370]](https://mwpro.co.uk/wp-content/uploads/2024/08/pexels-steve-27594600-1024x683.webp "(Updated) Auto upgrade of shared calendars from legacy MAPI model to modern REST model [MC1287370] 1")
Posted inMicrosoft 365 suite
(Updated) Auto upgrade of shared calendars from legacy MAPI model to modern REST model [MC1287370]
Message ID: MC1287370 (Updated) Updated April 22, 2026: We have updated the timeline and content. Thank you for your patience. [Introduction]Microsoft is introducing an automatic upgrade for shared calendars in Outlook and Exchange Online, transitioning from the legacy MAPI-based model to…
![(Updated) Engage is retiring live events powered by Teams Live Events effective April 27th, 2026 [MC1227085]](https://mwpro.co.uk/wp-content/uploads/2025/06/pexels-heyho-7546602-1024x683.webp "(Updated) Engage is retiring live events powered by Teams Live Events effective April 27th, 2026 [MC1227085] 2")
![(Updated) Auto upgrade of shared calendars from legacy MAPI model to modern REST model [MC1287370]](https://mwpro.co.uk/wp-content/uploads/2024/08/pexels-bess-hamiti-83687-36487-1024x683.webp "(Updated) Auto upgrade of shared calendars from legacy MAPI model to modern REST model [MC1287370] 3")
![Auto upgrade of shared calendars from legacy MAPI model to modern REST model [MC1287370]](https://mwpro.co.uk/wp-content/uploads/2025/06/pexels-mccutcheon-1209843-1024x683.webp "Auto upgrade of shared calendars from legacy MAPI model to modern REST model [MC1287370] 4")
![M365 and Microsoft Teams: Unified management of app and agent availability in Teams, Outlook, and the Microsoft 365 app [MC796790]](https://mwpro.co.uk/wp-content/uploads/2025/06/pexels-yankrukov-5215398-1024x683.webp "M365 and Microsoft Teams: Unified management of app and agent availability in Teams, Outlook, and the Microsoft 365 app [MC796790] 5")
![(Updated) Microsoft Teams: Rule-based enablement of Microsoft 365 third-party apps in the Teams admin center [MC1085133]](https://mwpro.co.uk/wp-content/uploads/2024/08/pexels-pachon-in-motion-426015731-16931380-1024x683.webp "(Updated) Microsoft Teams: Rule-based enablement of Microsoft 365 third-party apps in the Teams admin center [MC1085133] 6")