#!/usr/bin/perl

use strict;
use warnings;

my $dir = 'C:\Tickets';

chdir $dir
    or die "Error - Please check that $dir exists and is accessible.\n";

my @fileList = glob '*Closed*';

foreach (@fileList) {
    next if -d;
    my $oldname = $_;
    s/Closed/Open/;
    rename $oldname, $_;
}