In this video tutorial we will show you how to enter a license key in avast.
Right-click on the Avast icon and choose “Registration information”.
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In the following window, in the “Maintenance” tab, click “Insert avast! Pro Antivirus / Internet Security license file”. In next window, choose license key file from your hard drive, then press “Open”.
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If your license is not active or banned, choose another one.