I had this for the past few days. I think I managed to fix it for myself.
It seems to be connected to BE, since lot of people report no problems on unprotected servers.
Here are the things I tried in order to get rid of the issue (always checked few servers):

1. Restarts (PC, Router) = no luck
2. Verify game = no luck
3. Admin mode = seemed to work, but only for a bit
4. Reinstall = no luck
5. Putting WHOLE steamapps/DayZ folder on exceptions list in antivir (AVG) AND switching firewall (comodo) to game mode = 5h without problems so far.