Using a license file from an unverified source is counterproductive to the goal of "antimalware" software:
: Avast offers 30-day free trials for its Premium Security suite, allowing you to test features legally. avast antivirus license file till 2038
: Avast frequently updates its database. Once a shared license file goes viral, the company blacklists the key, causing your protection to disable itself without warning. Using a license file from an unverified source
