Well, more perlish way to do some of this:

 if ( /^Subject:\D+(\d+)/ ){
# if you can be sure of the '#' before the digits, use this
# if ( /^Subject:.*#(\d+)/ )  not that it buys you much
      push @subject, $1;
      next;
  }     # if /subject
...
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push is much better than your $i++ which may be getting messed up, the way your snippet looks. I'm guessing your open(OUTPUT ... is supposed to be outside the while {...}.

Not as snazzy as the ever terse, er, tidy io's suggestion, but:

if ( /\s*Out Comments\s*(.*)$/ ) {
  push @out_comments, $1;
  while (<>) {
# quit on a blank line or -------
    last if /^\s*$/ or /^\s*[-]+\s*$/;
    s/^\s*//;   # get rid of spaces at the beginning
    push @out_comments, $_;
  }
  next;
}   # if /Out Comments/
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not the 'strictest' of methods (re-while-ing the <> is frowned on by pendants) but if you're confident of your data format, it works. I get the impression you expect only one msg per email, so your arrays aren't needed, so scalars might be better (that is, $i is usually ends up '1'). Just do "$subject = $1;" and "$out_comment .= $_;" for the inner while loop. You'll avoid typos by:

$output_str = "@subject[$j];@failed[$j];@monthi[$j]/@dayi[$j]/@yeari[$
+j];@routerval[$j];" .
          "@tag[$j];@montho[$j]/@dayo[$j]/@yearo[$j];@lotCode[$j];@com
+mentso[$j]\n";
# or, if you've gone to scalars
$output_str = "$subject;$failed;$monthi/$dayi/$yeari;$routerval;" .
          "$tag;$montho/$dayo$/$yearo;$lotCode;$commentso\n";
    
print OUTPUT $output_str;
  print $output_str;
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And, last but definitely not least; perl -w/use strict, if you're gonna use the tools, use them *safely*. You'll be glad you did later on.

a