Another interesting spam mail filtered out by Thunderbird. It's a trojan horse hiding under the name of Microsoft Security updates that will compromise your antivirus and firewall software leaving it free for all to disturb your computer. Again don't open such email even if it came from your dad. Besides, they can't even spell properly. Better go to microsoft update and download it yourself.

Norton AntiVirus removed the attachment: update.zl9.
The attachment was infected with the Backdoor.Xordoor virus.