Hello,
I've found the solution to the problem of Windows Explorer not refreshing. Check if you have folders or files stuck on synchronization with cloud or network services. It looks like the Explorer hangs on such files or folders and constantly checks their status causing it to stop refreshing local files. The best thing to do is to temporarily disable the service causing the problem, clean its locally cached files, and re-enable it again. For me, it took only one file on iCloud to freeze the Explorer, hinder the functioning of some of the apps, and block the system from turning off. I hope it will help someone dealing with this problem.