Hi Brett DeCarion
Good day! Thank you for posting to Microsoft Community. We are happy to assist you.
I am truly sorry for the inconvenience this issue has caused you. Based on the description, I understand that you have concerns regarding the date for end of support for legacy Outlook for Mac client as it is different from the end of support for classic Outlook for Windows client.
Please be informed that Outlook for Mac and Outlook for Windows are two separate products of Outlook product group. They have individual and separate product development team due the OS differences. Each platform has its own set of challenges and requirements. By focusing on the new version of Outlook for Mac, Microsoft can allocate resources more efficiently to enhance features, performance, and security. This strategic decision helps ensure a better user experience for Mac users. Additionally, the underlying technology and architecture of Outlook for Mac and PC are different. Legacy Outlook for Mac uses Exchange Web Services (EWS), which is being phased out (Oct 2026) in favor of more modern protocols. This necessitates an earlier transition for Mac users to ensure continued support and security.
While it might seem ideal for both platforms to transition simultaneously, these factors contribute to the different timelines. Microsoft aims to provide the best possible experience for users on both platforms, even if the transition periods differ.
For further concerns, I kindly suggest reach Microsoft backend support team through the in-app support function. For details, please see: Contact support within Outlook for Mac - Microsoft Support.
Your kind understanding and cooperation are greatly appreciated.
Sincerely,
Roger Shen