avast! Virus Definitions allows for the convenient manual update your Avast anti-virus versions.

Avast! 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. Avast! represents a best-in-class solution for any Windows-based computer.

iAVS is a fast, small, incremental and fully automated update via the Internet. Updates are released at least twice a week.

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