每天都收到好幾封含病毒的信

信件標題如下,夾帶壓縮檔,裡面的執行檔大多含木馬
寄件者多半偽裝成快遞公司或HP,Xerox...等
這種信要怎麼阻擋? 謝謝
jConnect fax from "874-844-3673" - 27 page(s), Caller-ID: 874-844-3673
FW: Complaint Case CGCVCS64YFMMC32
Scanned Image from a Xerox WorkCentre
Your package is available for pickup ( Parcel 50GHTKC5 )
Corporate eFax message from "797-873-4357" - 3 pages
Fiserv Secure Email Notification - KSTC4KHWCJ19Q7U
[virus Win32/PSW.Fareit.A trojan] Please respond - overdue payment