avast! Professional Edition is a complete ICSA certified antivirus package for small office home office use - SOHO.Protect your system and valuable data against computer viruses with Avast! Professional Edition.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.