use Win32::OLE;
use Win32::OLE::Const 'Microsoft Outlook';

my $outlook = new Win32::OLE('Outlook.Application') or die "Could not open Outlook Application!\n";

my $msg = $outlook -> CreateItem(0);
unless ($msg){ die "Outlook is not running, cannot send mail.\n"; }

$msg->{'To'}         = 'test@domain.de';
$msg->{'Subject'}     = 'Betreff';
$msg->{'BodyFormat'} = 'olFormatHTML';
$msg->{'HTMLBody'} = 'Dies ist ein <b>Test</b>';

my $attach = $msg->{'Attachments'};
$attach->add('c:\anhang.txt');

$msg->Display();