follow the path the back slashes are the separators
C:\Documents and Settings\All Users\Application Data\Avg8\update\download
so open my computer, double click you hard drive c: to open it, then double click "documents and settings" in the list of folders you see, and keep going along the path until you get to the final folder...
once in the final folder select the view menu and set the view to be details, then click on the column header where it says "type" to sort the files into order of type. you should then be able to click on the first CTF file once then find the last ctf file then hold down the shift key and click on that once. That should select all the files between the two you have clicked on... then press delete to remove them and run the AVG update again.