If its always open on your desktop, make sure that you are only using the current, open instance of Excel, set your worksheet=ActiveSheet and don't close the worksheet or workbook before terminating your script.

my $Excel = Win32::OLE->GetActiveObject('Excel.Application')||
die "You gotta have it open first!!\n";
my $Sheet = $Excel->{ActiveSheet};
[download]

C-.

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Flex the Geek