I am trying to merge 2 programs I have made to one .jar file. One program is a .jar written in java and the second one is an .exe written in c++. I put both files to the new .jar, wrote this code but it didn't work. When this code was exported to .jar and executed neither of 2 files ran and I got error "no main manifest attribute, in merged.jar" in cmd. Though it worked perfectly when run in eclipse. public class main { public static void main(String[] args) { try { Runtime.getRuntime().exec("cmd /c project1.jar"); Runtime.getRuntime().exec("cmd /c project2.exe"); } catch(Exception exce) { /*handle exception*/ } } } Any idea how to fix this or is there another way to do it? I am new to java, so can't think of anything good. Maybe it would be possible to drop these files to a temporary location in windows and delete them after they're executed?