# Hytale Server Troubleshooting (/docs/hytale/fix-issues)



import { Step, Steps } from 'fumadocs-ui/components/steps';

Server Won't Start [#server-wont-start]

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

**Fix:** Install Adoptium Temurin JDK 25.

"Failed to Connect" [#failed-to-connect]

**Cause:** Port not forwarded or wrong protocol.

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

Authentication Failed [#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 [#players-cant-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 [#quicnetwork-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 [#high-ram-usage]

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

Config Changes Not Applying [#config-changes-not-applying]

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

Related Guides [#related-guides]

* [Server Configuration](/docs/hytale/server-config)
* [Performance Guide](/docs/hytale/optimize-performance)