Microsoft has recently changed text on their RPC over HTTP End-Of-Life page that originally claimed it will not allow Outlook 2007 to connect to Office 365. The new text has been updated to say

RPC over HTTP, also known as Outlook Anywhere, is a legacy method of connectivity and transport between Outlook for Windows and Exchange. In May 2014, Microsoft introduced MAPI over HTTP as a replacement for RPC over HTTP.

Starting on October 31, 2017, RPC over HTTP will no longer be a supported protocol for accessing mail data from Exchange Online. Starting on this date, the following conditions will apply:

Microsoft will not provide support for RPC over HTTP issues (regular or custom). No code fixes or updates to resolve problems that are unrelated to security will be released.

Additionally, for Office versions that support MAPI over HTTP, Microsoft may elect to override existing registry keys that customer are using in order to force RPC over HTTP use.

Keyword here: support. This essentially means that nothing will happen to users of Outlook 2007 and Office 365, but Microsoft will no longer support the protocol (AKA they won’t support Outlook 2007 connections)

It is still a good idea to move users away from Outlook 2007. We feel any calls to Office 365 with Outlook 2007 running will be met with resistance from the support staff. Additionally, Microsoft may change their stance on this in the future.

Use this Powershell script to check all your tenants for Outlook 2007 connections.

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