Just make a shortcut of the file and place it to
Startup folder (which u'll find in Programs folder)
or just open regedit and goto any of following keys:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
and in right-side pane create a new String value with any name and paste the path of the EXE file in its value