A while back Microsoft announced a change that would deprecate RPC over http from Exchange Online in favor of the more modern MAPI over http. It’s officially happening October 31, and as we get closer to the deadline we want to remind clients that this will affect anyone connecting to Exchange Online with legacy Office 2010 or Office 2013. In order to leverage MAPI over http, your Office implementation must be one of the following build versions:
- Office 2010 build 14.0.7164.5002 or later
- Office 2013 build 15.0.4779.1002 or later
- Office 2016 MSI build 16.0.4312.1001 or later or CTR build 16.0.6568.20xx or later
That said, patches for all Office versions were released in December 2015 in order to convert from RPC to MAPI. With that much lead time, few of our clients should be affected. Be sure, however, that everything is patched accordingly if you are still using these versions of Office with Exchange Online.
This support article will help you determine what version of Office you are running.