Just put this application where your Setup.exe file exists. Being always on top, it will run that Setup.exe file. It takes the serial numbers from the Serial.txt file and makes individual buttons as many as the serial number is separated by space.
Just click the buttons to copy the serial numbers and paste them into your program.
It will not run if the files Setup.exe and Serial.txt do not exits at its path. Save the Serial.txt file as- first line: your program name, second line: serial numbers (separated by space).
...