With the Arma2OA and Steam integration everyone's GUID has changed with the latest beta patch and you need to update yours! If you don't have latest beta installed. Read this thread first! 1) Start DayZero Launcher. Don't have it? Get it here! 2) Click versions and make sure you are using the latest version of the Launcher. Update it and restart if needed or click Done. 3) Click Settings and select your GUID with the mouse and copy the text (CTRL-C or right mouse click menu). 4) Go to https://zombies.nu/community/account/preferences and paste your new GUID to the correct field and click Save Changes. 5) You guessed it - bacon. Keep in mind that DayZ Commander or other similiar softwares haven't yet updated to support the new GUIDs.