I've downloaded the arma 2 Operation Arrowhead 1.60 update 3 times now and each time its 700mb and the computer says its empty.
I have downloaded on 3 separate computers and tryed extracting them and they all have the same results.
http://www.arma2.com/supply/game-updates/756-arma-2-combined-operations--operation-arrowhead--reinforcements-patch-1.html
I've downloaded from the normal and 2 different mirrors aswell.