How to fix the “Exception in server tick loop” JSON error?

Server booting into “Exception in server tick loop”? In most cases, a corrupted JSON file is the culprit. Upgrade your experience on our premium Minecraft hosting.

Prerequisites

• Access to your Oxygenserv panel (login and password)
• FTP/SFTP access (e.g., FileZilla) for backup and edits
• Admin rights on the server
• 5–10 minutes of planned downtime
• A proper text editor (Notepad++, VS Code), not Word

Step-by-step

1. Stop the server cleanly
   Log into the Oxygenserv panel and open the “Console” tab. Click the red “Stop” button and wait for the “Server stopped” line in the logs. If it hangs for more than 60 seconds, use “Force stop” once. Do not proceed until the process is fully stopped.
2. Back up the sensitive JSON files
   Go to the “Files” tab and locate ops.json, usercache.json, and whitelist.json (or allowlist.json on newer versions). Download them to your PC as a safety copy. Create a local folder like “backup-json” dated today. This helps you restore names if needed.
3. Delete the corrupted JSONs
   In “Files”, select ops.json, usercache.json, and whitelist.json/allowlist.json, then click “Delete”. Confirm the action in the prompt. Do not delete any other file. If you hit a permission error, reconnect via FTP/SFTP and delete them from your client (right-click > Delete).
4. Start the server to auto-regenerate
   Return to “Console” and click the green “Start” button. The files ops.json, usercache.json, and allowlist.json/whitelist.json will be recreated during boot. Wait for the “Done” line with the startup time. If it still crashes, continue with the quick diagnostics below.
5. Restore OP and your allowlist
   Grant yourself OP from the console (no slash) with op YourName. Enable and fill the allowlist depending on version: a) 1.19+ : allowlist on then allowlist add YourName. b) Older versions: whitelist on then whitelist add YourName. In-game, use the slash forms: /op YourName, /allowlist add YourName or /whitelist add YourName.
6. Still crashing? Pinpoint the JSON error
   Open logs/latest.log and search for .json mentions with hints like “Expected”, “malformed”, or “syntax”. Valid JSON has no trailing commas and proper quotes. A minimal valid empty file is []. Also review any plugin/mod config.json, especially after a hard power cut.

Tips & optimization

– Prefer commands over manual edits: use op, allowlist add, etc., to keep JSON format correct.
– If you must edit JSON, validate it online and save as UTF-8 without BOM. Use [] to safely reset a file.
– Schedule automatic daily backups and before updates; keep at least 3 rotations.
– On 1.19+, use the allowlist: allowlist on and manage players with allowlist add/remove for better security.
– Avoid hard kills; always stop via the panel and wait for “Server stopped” to prevent JSON corruption.

FAQ

Will deleting these files wipe my worlds or inventories?

No. ops.json, usercache.json, and whitelist.json/allowlist.json do not contain world data. They store operators, player cache, and allowed players. Your worlds (world, world_nether, etc.) and inventories remain intact.

I only see allowlist.json, not whitelist.json. Is that normal?

Yes. Recent versions renamed whitelist.json to allowlist.json and the related commands to allowlist. Use allowlist on, allowlist add Name, and allowlist remove Name.

Why do slash commands fail in the panel console?

Panel consoles expect commands without the slash. Use op Name, allowlist add Name or whitelist add Name. The slash versions (/op, /allowlist) are for in-game chat.

You got this. Follow the steps, boot cleanly, and your server will be back without the JSON crash. Need help? We’ve got your back.

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