This error can be caused by EAC failing to connect. Please ensure that your anti-virus/firewall is correctly configured to allow EAC to pass through. The way to do this will likely vary from program to program, so we recommend you refer to your software’s help section for details on how to do this.
If this does not work, you may need to repair EAC. You can do this by heading into the game’s main installation folder, then into the EasyAntiCheat folder. Right-click EasyAntiCheat_Setup and ensure you run this as an administrator. You’ll then need to click “repair” and let it run.