Is the Day Z mod compatible with the standalone release of Day Z

I just got this working myself, although it took some help from the internet to get it working.

• Install Arma 2 and Arma 2: Operation Arrowhead.
• Close Steam completely, and then rerun it as an administrator (this is required to launch Arma 2 for the first time. You'll get a bad serial key error otherwise)
• Create folder called @DayZ in C:\Program Files (x86)\Steam\steamapps\common\arma 2 operation arrowhead
• Create a folder inside of that folder called Addons, and then download all the DayZ mod files from the DayZ website into that folder (So they should be located in C:\Program Files (x86)\Steam\steamapps\common\arma 2 operation arrowhead\@DayZ\Addons)
• Extract the files into the Addons folder. Make sure they are in the top level of the Addons folder or Arma 2 won't be able to find the files.
• Launch Arma 2 (you need to run Arma 2 first in order for Arma 2: Combined Operations to work, which is required for DayZ.
• Launch Arma 2: Operation Arrowhead from the Steam library, and run it as Arma 2: Combined Operation

That's all you'll need to do to get DayZ working. Chances are you'll want to filter out the non-DayZ games, which you can do by opening the Filter menu and setting mission to DayZ.

Sources: this video, this thread, and this thread.

The servers show day or night depending on the actual, real-world time of the server.

Many DayZ servers show the timezone (as an offset from GMT/UTC) that server is set for. For example, the server DayZ - US #00 (1.7.2.3/95251) [REC][GMT-5] is located in GMT-5, whose current time can be found here. At the time of this writing, it's 10:30PM there, so that server will have night.

If the server does not display the timezone in the server-name, the best you can do is join servers located in a part of the world that currently has daylight. A lot of them change the timezone, though, so this method is not fool-proof.