Since the 6.0.1 hotfix, Squad's Steam Community discussions have seen a noticeable rise in reports of "Authentication timed out" and "Heartbeat Timeout" errors, along with players getting stuck on the loading screen when trying to join a server. If you run a Squad server and are seeing players report this, here is what is actually going on and what to check.
What these errors actually are
Squad uses Epic Online Services (EOS) alongside Easy Anti-Cheat (EAC) for authentication and anti-cheat verification when a player joins a server. "Authentication timed out" and "Heartbeat Timeout" both point to that handshake between the player's client, Epic's authentication servers, and your game server not completing in time, not to a problem with the map, the mod list, or the mission rotation.
Because this step depends on your server successfully reaching Epic's services, not just the player reaching your server, the cause is not always something visible from the server console. It can look identical whether the problem is on the player's end, your server's network path, or Epic's own service having a rough moment.
What to check first
Server clock accuracy. Authentication handshakes that involve token verification are sensitive to system time drift. If your server's clock has drifted, even by a small amount, that can cause tokens to be rejected as expired before they should be. Confirm NTP is syncing correctly on the server.
Outbound connectivity to Epic's services. Your server needs a stable outbound connection to EOS endpoints for this handshake to complete. A firewall rule that is blocking or rate-limiting outbound traffic on the wrong port will produce exactly this symptom, an authentication step that hangs and times out rather than failing immediately with a clear error.
Whether it is happening to everyone or a subset of players. If it is isolated to specific players, the more likely cause is on their end (their own connection to Epic's services, or a corrupted local EAC install that a client-side EAC reinstall can fix). If it is happening broadly across your player base at the same time, that points more toward either your server's connectivity or Epic's services having an outage, which does happen periodically across live service games that depend on a third-party authentication layer.
Recent hotfix timing. If the errors started right after 6.0.1, it is worth checking the official Squad channels for any acknowledged EOS-related issue tied to that update specifically, since server-side fixes for authentication layer problems are outside what an individual server owner can patch and depend on the developers or Epic resolving it upstream.
What this is not
This is not a mod conflict, a Layers.cfg problem, or a server performance issue. Those produce different symptoms (crashes, gameplay bugs, or stutter) rather than a failure at the authentication step before a player even loads into the map. If your server is otherwise running normally and only the join handshake is failing, the EOS/EAC layer is the right place to keep looking rather than server configuration.
Related reading
Related reading: Squad server hosting plans with 8 to 32GB tiers across four regions, NVMe storage, and DDoS protection included.
FAQ
Is "Authentication timed out" a server-side or client-side problem in Squad? It can be either. The handshake involves the player's client, your server, and Epic's authentication services, so the cause is not always visible from just the server console.
Did the 6.0.1 hotfix cause EOS authentication issues? Community reports on Steam Community discussions noted a rise in these errors after that update, though this is a third-party authentication layer issue rather than something a server config change can directly fix.
What is the first thing to check on the server side? Confirm the server's system clock is syncing correctly via NTP, since authentication token verification is sensitive to time drift.
If only some players get the error, is it still a server problem? Usually not. Errors isolated to specific players more often point to their own connection to Epic's services or a local EAC install issue on their end.
Can a server admin fix an EOS outage? No. If Epic's authentication services are having a broader issue, that resolves on their end, not through server-side configuration changes.