hello there ...
if you are having any problem while downloading an update from the launcher, you can try using manual patch and i think it works better than downloading an update through the game launcher directly
"How do you do that ?"
well, you can read here :
https://www.sea.playblackdesert.com/News/Notice/Detail?BoardMasterNo=1&CountryType=en-US&SearchType=&SearchText=&progressType=1¤tPage=1&BoardType=0&boardNo=282