Show us a little code.. Tell us how you created you exes..

It looks like you are using PAR, what else have you tried... do the exes run on their own from the cmd line etc...

Here is a small test case that I build to test your problem. I compiled both .pl files with perl2exe as I don't use par. I do not experience any problems with the code below. Basically exe1.exe calls exe2.exe 10 times and then exits.

exe1.pl

#! /usr/bin/perl

use strict;
use warnings;

print "Inside exe1 about to run exe2 (10 times)\n";

my $count = 0;

while ($count < 10) {
    system("exe2.exe");
    $count++;
}

print "Finished running exe2\n";
[download]

exe2.pl

#! /usr/bin/perl

use strict;
use warnings;

print "Inside exe2.exe\n";
[download]

Hope this helps.