use Win32::OLE;
$Win32::OLE::Warn = 3;
my $file  = "myfile.xls";
my $Excel = Win32::OLE->GetActiveObject('Excel.Application') or die 'Excel not running';
for my $n ( 1 .. $Excel->Workbooks->Count) {
    print $Excel->Workbooks($n)->Name , "\n";
    $Excel->Workbooks($n)->Close(1, $file, undef);
}
$Excel->Quit();