Here is the process for Avast Antivirus Download Manually -
Select Program from the drop-down menu that appears after you right-click the Avast symbol that is located in the notification area of your Windows taskbar. If your Avast Antivirus doesn't begin automatically checking for updates, you can force it to do so by clicking the Check for updates button. Please be patient while your Avast Antivirus software looks for and then installs any available application updates.

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