Virus is doing many things. Create Many *.lnk file same name as the folders, while the hidden folders(will be hidden and system attributes), and of course, an Autorun.inf file. The avast detects, but it infects.
Please Update Database.
Well, can you give more info?
Name of the virus.
Version of your avast and virus definitions?
Did you send the file to www.virustotal.com to check?
Please Update Database.Impossible unless you send a sample to avast lab......do you have a sample ?