At first i write the whole error message so you can check if you have the same issue or not :
"Failed to download the file.Check your network(ISP authentication, NAC, firewall, antivirus and other settings) and try again. ........ \Minimap_Baekchung.upk.zip(5664)"
I tried all suggestions in forum and support page but they didnt work for me .So i gave up downloading new launcher ; and used old one till yesterday. From yesterday i must download the new one ; old launcher wasnt working. First i tried the solutions here on support page again ; (https://support.bladeandsoul.com/hc/en-us/articles/207539943-Errors-E01005-E02018-E02015-E02016-E02019-5385-5664)
Then i tried to use a vpn ( vpnbook germany server PTTP) and now i can download the game.
Especially for users connecting the game from Turkey and other countries which has bad quality DSL ; i suggest thist method.