Hytale Server Troubleshooting

Server Won't Start

Cause: Wrong Java version. Hytale requires Java 25 specifically.

Fix: Install Adoptium Temurin JDK 25.

"Failed to Connect"

Cause: Port not forwarded or wrong protocol.

Fix: Forward UDP port 5520. Hytale uses QUIC over UDP, NOT TCP.

Authentication Failed

Cause: Server not authenticated with Hytale services.

Fix:

1. Run /auth login device in server console
2. Visit accounts.hytale.com/device and enter the code
3. Run /auth persistence Encrypted to persist across restarts

Players Can't Connect After Restart

Cause: Auth not persisted.

Fix: Set AuthCredentialStore.Type to "Encrypted" in config.json, or run /auth persistence Encrypted.

QUIC/Network Issues on Windows

Some Intel/Realtek NIC drivers have QUIC compatibility issues.

Fix: Use --transport TCP as a fallback in startup parameters. Or test with a USB Ethernet adapter.

High RAM Usage

Fix: Reduce MaxViewRadius from 32 to 12 in config.json. This is the #1 RAM driver.

Config Changes Not Applying

Fix: Stop the server before editing. The running server can overwrite changes.

Related Guides

• Server Configuration
• Performance Guide