The error means your server rejected the HC’s login token. The server said, "You are not running a legitimate copy of Arma 3, or your Steam credentials are invalid."
Post your server.log and HC launch script in the comments below. Do not post your RCon password. arma 3 headless client steam authentication failed hot
In server logs, a "Hot" error usually indicates an immediate disconnection or a critical security failure. You cannot ignore this; the HC will never process AI if this error persists. The Top 5 Fixes (Ranked by effectiveness) Fix #1: The Steam Beta Branch Mismatch (90% solution) The most common cause of the "Authentication Failed" error is a version mismatch between your Dedicated Server and your Headless Client . The error means your server rejected the HC’s login token
Published by: Dyslexic Geek | Difficulty: Advanced | System: Windows Server / Dedicated Box In server logs, a "Hot" error usually indicates
If you are reading this, you have likely spent the last hour staring at your Arma 3 server console, watching the Headless Client (HC) connect, immediately disconnect, and vomit a red error message: