use Win32::OLE qw(in with);
use Win32::OLE::Const 'Microsoft Excel';
use warnings;

#Content-Type: text/html;

$Win32::OLE::Warn = 3;    # die on errors...

# get already active Excel application or open new
$Excel = Win32::OLE->GetActiveObject('Excel.Application')
    || Win32::OLE->new('Excel.Application', 'Quit');  

# open Excel file
$Book = $Excel->Workbooks->Open("c:/users/david/desktop/RBLCopy.xls");