How do I run a program automatically when Windows starts?

Go to the Registry editor (regedit.exe) and open this location..

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run

Right click on the Right pane and choose New->String Value.

Change the name of New Value #1 to your application.
Double click on it and on the Value Data box write the path to your application with the executable.
example: "C:\Program Files (x86)\Spark\Spark.exe"