CTF files contain updates for the well-known AVG Anti-Virus Free and premium Internet Security software. Updates are automatically downloaded and applied when you use the Update feature; however, you can download updates in the form of CTF files from the AVG website. Furthermore, updates downloaded by the AVG Updater are downloaded in your user's Downloads directory as CTF files. In case the update fails, you can open these files manually and update the software.
Launch AVG Anti-Virus or AVG Internet Security. It should be running in the background but, if it's not, double-click the program's icon on your desktop.
Expand the "Tools" menu at the top of the AVG window and select "Update from directory." The Browse For Folder window pops up.
Use the integrated file browser to select the folder in which your CTF file resides and click "OK." The CTF file is opened and AVG is updated.
Wait until the update process is complete and close the AVG window.
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