use Win32;
use Win32::ChangeNotify;

my $appdir      = Win32::GetFolderPath(Win32::CSIDL_APPDATA);
my $notify_dir  = $appdir . '/Provider/Application/';
my $notify_file = $notify_dir . 'yourfile.txt';
my $notifyObj;

if ( $notifyObj = Win32::ChangeNotify->new( $notify_dir, 0, "LAST_WRITE" ) ) {
  print "We have a notifyObj object\n";
  $mw->repeat( 2000, \&checkNotify );
}
else {
  print "Application not installed on this machine\n";
}

sub checkNotify {
  my $rv = $notifyObj->wait(0);
  print "Found a change\n" if $rv == 1;
  $notifyObj->reset;
  if ($rv) {
     # DO what you need to do
  }
}