Can you ask the question a little bit clearer?
What I got from all that, is that a friend installed an antivirus onto his pendrive, and it auto runs and removes virus when he inserts it.
However onn most newer machines now a days the autorun feature is enabled by default so that doesn't really work on newer operating systems.
But a majority of machines still use xp to this day, so I would suggest try it on a windows xp machine to see if your install works.
Here is a list of alternatives that you can try.
I myself use Avast and ClamWin when dealing with an infected computer.
1)Yaa u got it right
2)Some say its enable by default while some say its disabled by default.Well in my PC it was enabled by default & i hav disbaled it recently2avoid virus but it was enabled @the tym of trial.
3)Autorun feature isnt my prob here since my OS is XP & i can enable or disable it on my own accord.
4)u can see my reply post where i did provided further details2it. i.e. My link
5)yaa ur right many use xp till date & so do i as well as most of the ppl here.let me clear you wht i did last tym while installing it,okk.So here it is.1st i tried to download the same anti-virus file 4m the same source as the guy did but i think i left or missed something due2which it didnt worked,(actually i didnt knw in the 1st place tht this guy will b doing such stuff so i didnt saw properly which site he visited &wht he did).After tht i tried some anti-virus by installing in my flash drive but instead got installed in my C drive,thn i realised i hav done something wrong in doing it.tht's y i m asking u all ppl.
6)do these pendrive apps gets installed directly or is there anything2do before installing it?