avast! 4 Server Edition is the most powerful protection to fight virus infection of your Windows-based server or servers (for protection of Linux-based servers, please refer to avast! for Linux). It works both as a classic protection of file-servers and, via its optional plug-ins, as a protection of various subsystems running on the server, including electronic mail, firewall/proxy etc.

• avast! 4 Exchange Server Edition - antivirus for Mail & SMTP Servers
  
  Protection for Microsoft Exchange 2000 and 2003 Servers. Features high-performance scanning, superior scalability and support for clustering (even in Active-Active mode). Perfectly integrates with Exchange via Microsoft's own Virus Scanning APIs
  
  
  
• avast! 4 ISA Server Edition
  
  Antivirus solution for your MS ISA Servers (also works with MS Proxy Server 2.0). Provides real-time scanning of HTTP and FTP traffic at the gateway, greatly reducing the risk of infection from the World Wide Web (including web-based mails etc.).
  
  
• avast! 4 SharePoint Server Edition
  
  This plugin offers real-time scanning on the following Microsoft SharePoint server versions: MS SharePoint Portal Server 2001, MS SharePoint Portal Server 2003, and Windows SharePoint Services 2003.
  
  
• avast! 4 SMTP Server Edition
  
  The SMTP Server Edition works as a plug-in to the Microsoft SMTP Service (part of the IIS). It can be deployed on a machine that acts as a universal gateway (or border server) for scanning purposes only - no matter which mail server you actually use.
  
  
• antivirus avast! 4 Lotus Domino Edition
  
  avast! Lotus Domino Edition works as a plug-in to Lotus Domino Servers (Windows platform only). It provides on-access scanning of Domino mail traffic as well as on-demand scanning of Lotus Notes/Domino databases (.NSF files).