I am using

use Spreadsheet::ParseExcel;
use Spreadsheet::WriteExcel;
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Yes, there is a sheet named Sales in one of the formulas. From what I have read, this should be possible.

Yes, their are two sheets. One named "How_Am_I_Doing" and the other "Sales".
There are numerous other cells, that have other formulas, for instance on sheet Sales there is one '=D3*E2, which calculates just fine. But all the cells with worksheet links cause errors, by removing those cells from the spreadsheet, everything writes fine. Here is some more of the code:

foreach my $sheet (keys %$storage_book){
  my $dest_sheet = $dest_book->addworksheet($sheet);
  foreach my $row (keys %{$storage_book->{$sheet}}){
    foreach my $col (keys %{$storage_book->{$sheet}->{$row}}){
      if ($sheet eq "Sales") {
        if ($storage_book->{$sheet}->{$row}->{$col} eq 'Agent') {
          $getsales=1;  #next row start getting sales
        }
        elsif ($storage_book->{$sheet}->{$row}->{$col} eq 'Total') {
          $getsales=0; #stop getting sales
        }
        #GET THE AGENTS NAME
        if (($getsales ==1) && ($col == 0)) {
         #performs a sql query here
        }
      }
      if (($getsales == 1) && ($col == 4) && ($sheet eq "Sales") && ($
+agentname eq "Agent")) {
        $dest_sheet->write($row, $col, $exchange_rate);
      }
      elsif (($getsales == 1) && ($col == 2) && ($sheet eq "Sales")) {
        if ($agentname eq "Agent") {
          $dest_sheet->write($row, $col, $storage_book->{$sheet}->{$ro
+w}->{$col});
        }
        else {
           $dest_sheet->write($row, $col, $cdnsales);
        }
      }
      elsif (($getsales == 1) && ($col == 3) && ($sheet eq "Sales")) {
        if ($agentname eq "Agent") {
          $dest_sheet->write($row, $col, $storage_book->{$sheet}->{$ro
+w}->{$col});
        }
        else {
          $dest_sheet->write($row, $col, $usdsales);
        }
      }
      else {
        if (($row == 0) && ($col == 1) && ($sheet eq "Sales")) {
          $dest_sheet->write($row, $col, $startdate);
        }
        elsif (($row == 0) && ($col == 3) && ($sheet eq "Sales")) {
          $dest_sheet->write($row, $col, $today);
        }
        else {  ###HERE IS LINE 265
          $dest_sheet->write($row, $col, $storage_book->{$sheet}->{$ro
+w}->{$col});
        }
      }
    } # foreach column
  } # foreach row
} # foreach sheet

$dest_book->close();
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