#!/usr/bin/perl

use strict;
use warnings;

my $dir = 'C:\Tickets\';

my @fileList = glob "${dir}*Closed*";

foreach (@fileList) {
    next if -d;
    my $oldname = $_;
    s/Closed/Open/;
    rename $oldname, $_  or
        $_ = $oldname,
        warn $_, ' not renamed: ', $!;
}