Not to be confused with Windows AutoPlay These are Registry Key that can be used to set programs to automatically run on system startup.
Autorun Registry Keys
C:\Windows\system32\config\Software\Microsoft\Windows\CurrentVersion\Run
C:\Windows\system32\config\Software\Microsoft\Windows\CurrentVersion\RunOnce
C:\Windows\system32\config\Software\WOW6432Node\Microsoft\Windows\CurrentVersion\Run
C:\Windows\system32\config\Software\WOW6432Node\Microsoft\Windows\CurrentVersion\RunOnce
C:\Users\<User>\ntuser.dat\Software\Microsoft\Windows\CurrentVersion\Run
C:\Users\<User>\ntuser.dat\Software\Microsoft\Windows\CurrentVersion\RunOnce
Viewing Autoruns
A diagnostic software for viewing which software automatically starts up in windows. Windows has alot of trouble pinpointing auto-startup software due to its scattered ecosystem and its push on Backwards Compatability allowing old features to remain present.
Installation
https://learn.microsoft.com/en-us/sysinternals/downloads/autoruns