avast! 4 Professional Edition is a collection of award winning, high-end technologies that work in perfect synergy, having one common goal: to protect your system and valuable data against computer viruses. It represents a best-in-class solution for any Windows-based workstation. This page demonstrates its most important features and provides links to further resources.

key features:
· Antivirus kernel
· Automatic updates
· Simple User Interface
· PUSH updates
· Enhanced User Interface
· Virus Chest
· Resident protection
· System integration
· Script blocker
· Command-line scanner
· P2P and IM Shields
· Integrated Virus Cleaner
· Network Shield
· Support for 64-bit Windows
· Web Shield
· Internationalization

Requirements:
· For a computer running Windows 95/98/Me: 486 Processor, 32MB RAM and 50MB of free hard disk space.
· For a computer running Windows NT 4.0: 486 Processor, 24MB RAM and 50MB of free hard disk space and Service Pack 3 (or higher) installed
· For a computer running Windows 2000/XP Workstation (Not Server): Pentium class Processor, 64MB RAM (128MB recommended) and 50 MB of free hard disk space
· For a computer running Windows XP 64-bit Edition: An AMD Athlon64, Opteron or Intel EM64T-enabled Pentium 4 / Xeon processor, 128MB RAM (256MB recommended) and 50 MB of free hard disk space
· For a computer running Windows Vista: Pentium 4 processor, 512MB RAM and 50 MB of free hard disk space
· The program itself requires about 20MB of hard disk space; the remainder of the recommended space is reserved for the virus recovery database file and its index (VRDB, also known as the "integrity database" from the previous version).
· A functional MS Internet Explorer 4 or higher is required for the program to work.


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