These are the "Top 10 signs your computer may be part of a Botnet", and and most of them apply to Windows 10. In no particular order… 1) Your fan kicks into overdrive when your computer is idle. This can indicate that a program is running / installing without your knowledge and using a fair amount of resources, including Microsoft updates. 4) Programs are running very slowly. This can be a sign that hidden programs are using a lot of your computer’s resources. 5) You cannot download operating system updates. When the operating system itself is the culprit, updates don't matter