Fix Hytale Mod Compatibility Issues
Mod compatibility problems can prevent your Hytale server from starting or cause crashes during gameplay. This guide will help you identify, resolve, and prevent mod conflicts for a stable modded experience.
Understanding Mod Compatibility
Mod compatibility issues typically arise from:
- Version mismatches between mods and game
- Conflicting API changes or dependencies
- Overlapping functionality between mods
- Wrong file type or folder (plugins are
.jarfiles inmods/) - Outdated or abandoned mods
Version Conflicts
Mods built for different Hytale versions
Dependency Issues
Missing or incompatible required libraries
API Conflicts
Mods modifying the same game systems
Solution 1: Match the Mod to the Server Version
Every plugin and asset pack states the server versions it was built for in its manifest.json (ServerVersion). A pack that targets an older server still loads, but the server logs "One or more asset packs are targeting an older server version" and tells players with the hytale.mods.outdated.notify permission, which operators have, which ones are outdated. Treat that message as the first thing to fix after a game update: get the mod author's new build, or hold the server back.
Plugins are Java code, so a plugin built against an older server API can also fail with Java errors such as NoSuchMethodError when the API changed. Run /plugin list to see what is loaded, and check each plugin's page for the server version it supports.
Solution 2: Dependencies
A plugin can name Dependencies (required) and OptionalDependencies in its manifest, each with a version range. The server loads dependencies first and refuses a plugin whose dependency is missing or the wrong version. The two messages are:
Failed to load 'X' because the dependency 'Y' could not be found!: install the missing mod.Failed to load 'X' because version of dependency 'Y'(1.2.0) does not satisfy '>=1.3.0'!: update the dependency.
Load order follows each mod's manifest first: Dependencies and OptionalDependencies load before the mod, and LoadBefore names mods it must come ahead of. As the server owner you can add an order of your own with ModLoadOrder in config.json, a list of mod ids written Group:Name, each loaded after the one before it. An order that contradicts a dependency stops the server at boot with "Manual load order conflicts with plugin dependencies", and two mods that depend on each other stop it with "Found cyclic dependency between plugins".
Solution 3: Find the Conflict
Use this approach when no message names the culprit:
- Start the server with an empty
mods/folder. - Add mods one at a time and start the server after each.
- When it fails or misbehaves, remove the last mod you added.
- Read the newest file in
logs/for the error and stack trace.
To keep a mod installed but switched off, set "Enabled": false for it under Mods in config.json, and DefaultModsEnabled controls plugins that have no entry. To boot despite a broken mod, start with --ignore-broken-mods.
| Conflict type | What you see | Resolution |
|---|---|---|
| Same pack twice | Two packs with the same id: the server stops and reports a duplicate pack | Keep one copy, delete the other from mods/ |
| Two mods change the same thing | One mod's change is missing or the game behaves oddly | Test each alone, then keep one or find a compatible alternative |
| Missing or wrong dependency | The "Failed to load ... dependency" lines above | Install or update the dependency |
Solution 4: Read the Log
The server starts a new file in logs/ each time, named like 2026-10-16_08-30-00_server.log. Java errors that point at a plugin:
NoClassDefFoundError: a dependency is missing.NoSuchMethodError: the plugin was built for a different server API version.IllegalStateException: the plugin did something the server does not allow at that point.ConcurrentModificationException: the plugin is not thread safe.
For more detail, raise the log level. Start the server with --log <LEVEL>, or with --log <logger>:<LEVEL> for one logger (a comma separates several), or set it under LogLevels in config.json.
Prevention Strategies
Mod Selection Best Practices
- Choose actively maintained mods
- Check mod compatibility lists before installing
- Read recent reviews for known issues
- Prefer mods with good documentation
- Join mod communities for support
Testing Protocol
Follow this testing process before going live:
Local Testing
Test mod combinations on single-player first
Staging Server
Use separate server for mod testing
Gradual Rollout
Add mods slowly to live server
Community Resources
Compatibility Databases
Use these resources to check mod compatibility:
- Mod pages: check the server version a mod says it supports
- Community Spreadsheets: Player-maintained compatibility lists
- Discord Servers: Real-time compatibility discussions
- GitHub Issues: Track known bugs and conflicts
Getting Help
When requesting help with mod issues:
- Provide your complete mod list with versions
- Include relevant error logs and stack traces
- Describe the steps that reproduce the issue
- Mention any troubleshooting you've already tried
- Be patient - complex issues take time to diagnose
Pro Tip: Create a mod profile system where you can save different mod combinations. This allows you to quickly switch between mod sets for testing different configurations without manually reinstalling mods each time.
Emergency Recovery
If your server won't start due to mod conflicts:
- Move all mods to a backup folder
- Start the server to confirm it works vanilla
- Add mods back one by one until you find the culprit
- Check for updated versions of problematic mods
- Consider alternatives if conflicts persist
Maintain a stable and enjoyable Hytale server by properly managing mod compatibility and resolving conflicts before they impact your players' experience.