Hello,
I cant update WoW after last patch. After i press update button there is info under it “Initializing (20/211mb…40/211mb…60/211mb)” and after few seconds proces starting again and again and again. Tried few thing from support info but nothing helps 
After 10 min i get info " Something went wrong while trying to launch a program. Please try restarting the Battle.net desktop app. If that doesn’t work, try restarting your computer."
Edit: i found solution here https://us.battle.net/support/en/article/257703