Rust EAC Error Fix: Unacceptable Client Module Version & Connection Errors
Nothing is more frustrating than trying to join a server and getting kicked with "EAC Disconnected" or "Steam Auth Timeout". These errors can happen on both the client (your PC) and the server side.
Common Error Messages & Fixes
1. "EAC Disconnected" or "Easy Anti-Cheat Violation"
This means the anti-cheat system failed to verify your game files or connection.
Client Fix (Player)
- Close Rust completely.
- Go to your Rust installation folder: `\Steam\steamapps\common\Rust\EasyAntiCheat`.
- Run `EasyAntiCheat_Setup.exe` as Administrator.
- Select "Rust" and click "Repair Service".
- Restart your PC.
Server Owner Fix
Ensure your server files are up to date. Sometimes a server update corrupts EAC files.
Run `app_update 258550 validate` in SteamCMD to verify server integrity.
2. "Steam Auth Timeout"
This error occurs when the server cannot verify your Steam ID with Valve's master servers.
For Players:
- Restart Steam: Log out and log back in. Steam's session token may have expired.
- Check Steam Status: Is Steam down? Check steamstat.us.
- Opt out of Steam Beta: Beta clients sometimes cause auth issues.
For Server Owners:
- Update Server: An outdated server version will fail to authenticate newer clients.
- Port Forwarding: Ensure the Steam Query Port (default 28016 or 28017 UDP) is open in your firewall.
3. "Packet Flooding: Player Tick"
Often caused by lag or bad internet connection, but can also be a server performance issue.
For Players:
- Use a wired Ethernet connection instead of Wi-Fi.
- Close bandwidth-heavy apps (Netflix, huge downloads).
For Server Owners:
If many players get this, your server might be overloaded.
- Check CPU Usage: Are you hitting 100%? Upgrade your hosting plan.
- Physics step: Sometimes `physics.steps` needs adjustment, but default is usually best.
- DDOS Protection: Ensure you have robust DDoS mitigation.
Blocked from a Secure server: TPM 2.0 and Secure Boot
Since March 2026, some Rust servers run in Secure mode and refuse connections from machines without TPM 2.0 and Secure Boot enabled. This is a server-side choice that lets Easy Anti-Cheat work at full strength, not an EAC malfunction on your machine. Secure servers show a Secure tag in the server browser, and clicking the server lists what is required and whether your system currently supports it.
- Check your side: most PCs from 2016 onward have TPM 2.0 hardware, but Secure Boot is often disabled. Both are toggled in UEFI firmware settings (the same requirements Windows 11 introduced, so Windows 11 machines usually pass already).
- Enable them: reboot into UEFI settings, enable TPM (sometimes named fTPM or PTT) and Secure Boot, and boot back into Windows. No Rust reinstall is needed.
- Or pick a regular server: Secure mode is opt-in per server. Servers without the Secure tag connect exactly as before.
- Server owners: requiring TPM and Secure Boot measurably cuts cheaters (Facepunch reported roughly 1 in 63 on secure servers versus 1 in 42 on regular ones) at the cost of excluding players who have not enabled the features. See the 2026 roadmap page for the current anticheat picture.
General Troubleshooting Steps
If you still can't connect, try these universal fixes:
Verify Game Integrity (Client)
- Right-click Rust in Steam Library > Properties.
- Go to "Installed Files".
- Click "Verify integrity of game files".
Flush DNS (Client)
Open Command Prompt as Admin and type: `ipconfig /flushdns`
Reinstall Rust (Last Resort)
Sometimes a fresh install is the only way to fix deep corruption.
Running a server and tired of constant errors? Move to managed Rust hosting from Supercraft where our automated systems handle updates and integrity checks for you.