На буржуйских форумах быстро начался вой и люди нашли простое эффективное решение: удалить проблемное обновление.
If you have MS office 2013 64 bit version and want to revert from version 15.0.5589.1001(September 12) to 15.0.5571.1000 (July 11). Please take steps below before running command prompt.
First, disable office updates: Open any Office app and navigate to File > More > Account > Update Options > Disable Updates. (You can enable this later when new update becomes available from Microsoft)
Next, open Command Prompt in admin mode.
Copy & paste command line below and press enter
"C:\Program Files\Microsoft Office 15\ClientX64\officec2rclient.exe" /update user updatetoversion=15.0.5571.1000