McAfee 比較早.
I use McAfee Anti-virus since DOS 5.0/6.0. It is nice software. The latest version is McAfee VirusScan 6.02 (Professional version even includes firewall). It has following features:

System Scan. This module looks for viruses on your hard disk as you work with your computer. It tracks files as your system or other computers read files from your hard disk or write files to it. It can also scan floppy disks and network drives mapped to your system.

E-Mail Scan. This module scans e-mail messages and message attachments that you receive via intraoffice e-mail systems, and via the Internet. It scans your Microsoft Exchange or Outlook mailbox. It works in conjunction with the Download Scan module to scan Internet mail that arrives via Simple Mail Transfer Protocol (SMTP) or Post Office Protocol (POP-3) sources. To use this module, you must install it from the Custom option in Setup.

Download Scan. This module scans files that you download to your system from the Internet. If you have enabled the Internet mail option in the E-Mail Scan module, this will include e-mail and file attachments that arrive via SMTP or POP-3 e-mail systems, which include such e-mail client programs as Eudora Pro, Microsoft Outlook Express, NetScape mail, and America Online mail. To use this module, you must install it from the Custom option in Setup.

Internet Filter. This module looks for and blocks hostile Java classes and ActiveX controls from downloading to and executing from your system as you visit Internet sites. It can also block your browser from connecting to potentially dangerous Internet sites that harbor malicious software. To use this module, you must install it from the Custom option in Setup.

HAWK: Hostile Activity Watch Kernel (HAWK) monitors your computer for suspicious activity that may indicate a virus is present on your system. As opposed to VirusScan, which cleans the virus, HAWK prevents viruses, worms, and Trojans from spreading further.