Troubleshooting Arma 3 Headless Client "Steam Authentication Failed" (2026 Updated Hotfix)
to allow the second account access to the Arma 3 license for the HC. 4. Basic Troubleshooting Steps arma 3 headless client steam authentication failed hot
arma3_x64.exe -client -connect=127.0.0.1 -port=2302 -password=HC_Password -nosound -noPause -skipIntro -noLogs -world=empty -port=2399 -profiles=HCProfile When a Headless Client starts, it automatically picks
(Note: I can run web searches for recent forum threads or specific log examples if you want; say “search” and I’ll fetch current guidance.) When a Headless Client starts
There are four primary causes for this specific error when dealing with Headless Clients:
This is a more advanced issue but a known cause of connection failures. When a Headless Client starts, it automatically picks a port for its own BattlEye communication, which is always the game port plus 14. For example, if your server runs on default port 2302 , your first HC will try to use port 2316 . The problem arises if you run multiple servers or if another service is already using that port.