I did not know there was an update because I downloaded the mod through six launcher but I use the actual game to select servers. So I was in the previous version of DayZ, I loaded into a server and it auto updated battle eye to 1.66 while loading. The solution may be that you need to revert to the previous version of DayZ (IDK how), join a battle eye enabled server, and it should auto update to 1.66, then you go back into six launcher and update to newest version of DayZ. EDIT: Nevermind that didn't stick for me, probably for no one else... Just play the previous version til fix?