Go
here and click "The Author's Site" link to download the file. The file name will end with .bin. Save it to an empty folder on your desktop.
After it's been downloaded and saved, right-click the taskbar AVG icon and then click "Open AVG User Interface".
When the AVG main window opens, click Tools - Update From Directory.
Browse to the desktop folder where you have the saved .bin file and then click OK.
AVG will update from that file.
You can delete the .bin file afterwards.
(Note: This procedure will work with the free version, so ignore the editor's note at the download site.)
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