I can’t, I just can’t i have been trying for 10 hours straight to download this battle.net app. I did EVERYTHING wiped out whole %appdata% and others, 0 battle.net files (even trying to install it on other disk), then I download new battle.net setup and it ALWAYS starts at somewhere 20% of instalation saying “Updating Blizzard Agent” and it is stuck there forever, I was even trying to download it from other sources but it was always the same issue. please help all i want is to play in overwatch 
(I have latest bios, latest drivers for everything)
try this method fixed my problem until blizzard comes up with a solution. 
Hotfix for Agent not installing