A billion ways to run code in Windows
Microsoft Windows has a scary number of routes to inject code into the running system. And large application suites have a proclivity to set up unnecessary applications to autorun on system start-up. Furthermore, uninstalling an application does not always get rid of the parts that it had planted into Windows itself.
A very useful utility to inspect what is running on the system and where it is being started from is Autoruns by Mark Russinovich, a Windows expert.
It has helped me many times.
— Oliver Frolovs, 2020