There are 13 files in that rar. same size 130kb different name and MD5

all 13 are detected by avast! as Win32:Dropper-gen

http://virusscan.jotti.org/en/scanresult/e6dff3c4747cf0fcd39bdb375e2b3fe13c1dfb8c

I think there is some misunderstanding/language problem here…what he is asking is in post 1 and 2

I scanned this file from context menu and avast showed no threat detected But when i added it to virus chest and scanned it again , virus was found ,see the first screenshot.
it quite confused me whether it's different between scanning from context menu and from virus chest?