Jim has several Windows 8.1 machines, and the keyboards on seven of them simultaneously stopped working. He found a fix for it, but he's wondering what happened. Leo said that it was probably an HP update that broke the HP keyboard drivers. They have a separate update from Windows that is always running enabling them to push updates on the fly. It sounds like their update ran afoul with Windows and caused the keyboards not to work. To turn off the HP updates, he should type Windows + Q, type "HP Update" and turn it off.
He could just have only one computer running the HP update and when it breaks, he'll know that's an update to ignore. That means he'll have to update them all manually, but it's worth protecting his network that way. It's what IT departments do.