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Microsoft O365 change requires some Windows users to upgrade Outlook by October 31, 2017

On Tuesday, October 31, 2017, RPC over HTTP (Remote Procedure Call over HTTP) will no longer be a supported protocol for accessing mail data from O365. Microsoft will no longer provide support or updates for Outlook for Windows clients that connect through this protocol and the user’s experience will deteriorate over time. Outlook apps for devices and Outlook 2016 for Mac are not affected by this change.

Outlook 2007 is only able to connect via the RPC over HTTP protocol.  Outlook 2007 users need to update their client to the most current version of Outlook 2016 (recommended) or Outlook 2013. Additionally, current users of Outlook 2016, Outlook 2013, or Outlook 2010 should ensure they have updated to the most current versions. ISC strongly recommends that all users of PennO365 run the latest version of Outlook 2016 for the best and most consistent user experience.

ISC has identified approximately 200 users that are using the RPC over HTTP protocol. We will contact school and center IT organizations directly regarding their impacted user populations by the end of business today, Friday, October 20.

RPC over HTTP is a legacy method of connectivity and transport between Outlook for Windows and Exchange. Microsoft introduced MAPI over HTTP as its replacement in May 2014. For more information about this change, see: