Are you guys on windows 10?
I always get error 4049 when I try to run the game and Cortana is working in the background. Open up Task Manager and look under Background processes. If Cortana is there, then right click Cortana and end click on End task. Cortana will respawn a few times in a matter of seconds, so just keep closing Cortana. When Cortana is tired and stops respawning (Cortana will respawn again later, fyi, but by then, GG won't mind 'cause you'll be in the game) - right click Blade and Soul launcher, click on Run as Administrator, then try to launch the game. If you still get error 4049...then maybe it's another program that's not getting along with GG.
Try: Window's key + R - type in MSCONFIG - Run - Services tab - Click Hide all Microsoft services - Disable All - OK - Restart
Run BnS as admin...now try again. If that doesn't work.....I've no clue. Keep contacting support. :(