If you are having problems connecting to The Dead Return or any other DayZ Mod server, take a look at this post. The December 2015 Arma2OA update messed up a few things. The good news is that you can use the Steam DayZMod link. DayZLauncher or your own batch file.
If you use the DayZMod link within Steam, everything should be fine (did you remember to run Steam as Administrator?)
If you use DayZLauncher, make sure you have version 0.1.3.4 or higher and try setting “Launch DayZMod as Steam App”. Click “Update Launcher” if necessary.
If you want to use a batch file to connect to The Dead Return, cut and paste the code below into DeadReturn.bat, make sure STEAMPATH and ARMA2PATH are correct, save it on the desktop and double-click!
@echo off REM Connect to The Dead Return set ip=220.127.116.11 set port=2302 set prams=-high -maxmem=2047 -noPause -nosplash -skipintro -world=empty SET _STEAMPATH=C:\Program Files (x86)\Steam SET _ARMA2PATH=C:\Program Files (x86)\Steam\steamapps\common\Arma 2 "%_STEAMPATH%\steam.exe" -applaunch 224580 "-mod=%_ARMA2PATH%" "-mod=EXPANSION;ca;@DayZ %prams% -connect=%ip% -port=%port%
Your friendly admin,