EA Javelin Anti-Cheat Error [4] and [1] — Cannot Enter Any Game Session
Bug Description
Since October 18, 2026, I've been experiencing an anti-cheat issue in Apex Legends. The game was working perfectly fine on October 17, and the problem started suddenly the following day.
I'm playing Apex Legends through Steam. The game launches successfully and reaches the main menu. However, the moment I attempt to connect to any session (Firing Range, Unranked Trios, etc.), I'm returned to the main menu with the following error:
The client is not running the anti-cheat, or has failed the anti-cheat authentication. [4]
I've also encountered a second error during my troubleshooting attempts:
The client failed an anti-cheat runtime integrity check. [1]
Extensive Troubleshooting Already Completed
Unfortunately, none of the following steps resolved the issue:
- Completely uninstalled and reinstalled Apex Legends.
- Verified the integrity of the game files through Steam.
- Completely uninstalled and reinstalled EA Javelin Anti-Cheat using the official installer multiple times.
- Ran Steam, Apex Legends, and the Javelin Anti-Cheat installer as Administrator.
- Ended all residual ACE/AntiCheat background processes through Task Manager.
Additional Information
This issue started suddenly despite the game working normally the previous day. I've already completed extensive troubleshooting, including reinstalling both the game and EA Javelin Anti-Cheat, without success.
I've attached screenshots of both error messages.
Could an EA representative please investigate this issue? I'd appreciate confirmation of whether this is a known problem and any additional troubleshooting steps that could resolve it.
Thank you.
