windows - how to install setup using batch file -

i trying run install exe using batch script

set var =abc.exe %var% 

my script shown above if write in script abc.exe installing if assign path variable , try run exe not installing

set var = abc.exe abc.exe 

abc.exe in current directory if batch script having abc.exe installing why if assign exe path var not installing

remove space between variable , executable name.

set var=abc.exe