Late last week I had a client call me about Word acting slow. After a quick checkup, I noticed that Word was using 25 – 40% CPU. I hadn’t received any other reports so I assumed it was a one-off and recreated the document. This sorted the issue for that particular computer.
Today I got the same report from a dozen more people. I started digging around in the documents that were having issues and noticed a drop in CPU usage when removing the header and footer. More specifically, removing images or objects in the header and footer.
Since I didn’t have the issue on a freshly installed computer, I began suspecting updates were the cause. Sure enough, after removing KB3114717 everything went back to normal.
Microsoft has pulled the update already and advises people to uninstall it.