My system was running fine, but once this update installs, I get a "busy" cursor about every other second, windows mail crashes when I try to open it as does windows search. When I run task manager, the antimalware service executable is using a ton of resources and I can't shut it down. I uninstalled the update once and my PC ran great for a week, then without any notification, it installed the update again and is now giving me an error when I try to uninstall it. I've uninstalled every other update on my machine, but cannot uninstall kb5009566. I am incredibly frustrated.