Yeah having this "session lost" issue as well. Im in the UK area, i have reinstalled dayz, reinstalled Battleye, reinstalled steam, verified game cashe and it dont really matter if its a full server or empty one, "session lost" just happens randomly, just when i join the server or been playing between 5 minutes to an hour and I also get "instruction at 0x memory could not be written" every time I close the game. checked with Memtest and i had no issues with memory hardware.

The issue started for me like 6 updates ago.. Kinda starting to get frustrated.