Avast Professional Edition is a complete ICSA certified antivirus software for your company. Avast! scans for viruses, worms, and Trojans: on demand - with two user interfaces (simple and enhanced - Outlook like UI allows user to set any feature of avast!, prepare and run tasks, store and check task's results), on access, e-mail, during boot time, in file explorer, and screen saver. It maintains virus chest. Features included: resident protection for IM programs (ICQ, MSN Messenger?) and P2P programs (Kazaa, DirectConnect?), enhanced support for Win32 EXE packers (UPX, PeShield?), and archives (ACE, ARC?), integrated virus cleaner, Internet mail protection support multiple SMTP server?True incremental and automatic updates (well below 100 KB) based on iAVS technology, update virus definition at least twice a week.

Version 4.1.389 fixes a bug in the Internet Mail provider that was causing its seldom crashes and fixes problems in the Standard Shield that were causing instabilities in some Win9x systems.