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

# open Excel file
#my $dir = "E:\\Automation Related\\Perl Scripts - ALL\\IMS_debugging\\Excel\\";
my $excelfile = 'UE_NW_Parameters.xlsx';
#my $Book = $Excel->Workbooks->Open($dir.$excelfile)
my $Book = $Excel->Workbooks->Open($excelfile)
  or die Win32::OLE->LastError();