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Minecraft Mod & Plugin Conflicts

This guide helps you identify and fix mod or plugin conflicts that cause server crashes, errors, or unexpected behavior.

Types of Conflicts

Section titled “Types of Conflicts”

Plugin vs Plugin

Section titled “Plugin vs Plugin”

Two plugins trying to do the same thing or accessing the same data. Common with:

  • Economy plugins
  • Permission plugins
  • Chat formatting plugins
  • World protection plugins

Version Mismatch

Section titled “Version Mismatch”

A plugin/mod built for a different Minecraft or loader version:

  • Plugin for 1.19 on a 1.20 server
  • Forge mod on a Fabric server
  • Outdated API dependencies

Missing Dependencies

Section titled “Missing Dependencies”

A plugin/mod requires another plugin/mod that isn’t installed:

  • “Missing dependency: Vault”
  • “Requires LuckPerms 5.4+“

Reading Error Logs

Section titled “Reading Error Logs”

Where to Find Logs

Section titled “Where to Find Logs”
  1. Console — Real-time in control panel
  2. logs/latest.log — Full session log in File Manager
  3. crash-reports/ — Detailed crash dumps (when available)

What to Look For

Section titled “What to Look For”

Key phrases in error messages:

PhraseMeaning
Caused by:The actual error — read this line
at com.example.mypluginWhich plugin caused it
NoClassDefFoundErrorMissing dependency
NoSuchMethodErrorVersion mismatch
NullPointerExceptionBug in the plugin (report to author)
Enabling PluginName then crashThat plugin is the problem

The Binary Search Method

Section titled “The Binary Search Method”

When you have many mods/plugins and don’t know which one is causing issues:

Step-by-Step

Section titled “Step-by-Step”
  1. Remove HALF of your plugins/mods
  2. Start the server
  3. Test — does it crash?
    • If crash → Problem is in remaining half
    • If works → Problem is in removed half
  4. Put back half of the suspect group
  5. Repeat until you find the culprit

Example

Section titled “Example”

You have 20 plugins:

  1. Remove 10 → Server works → Problem in removed 10
  2. Add back 5 of those → Server crashes → Problem in those 5
  3. Remove 2 of those 5 → Server works → Problem in removed 2
  4. Add 1 back → Server crashes → Found it!

Common Conflicting Plugins

Section titled “Common Conflicting Plugins”

Economy Plugins

Section titled “Economy Plugins”

Don’t run multiple economy systems:

  • ❌ EssentialsEconomy + Vault + CMI Economy
  • ✅ Pick ONE economy provider

Permission Plugins

Section titled “Permission Plugins”

Use only one permission system:

  • ❌ LuckPerms + PermissionsEx + GroupManager
  • ✅ Pick ONE (LuckPerms recommended)

Chat Plugins

Section titled “Chat Plugins”

Multiple chat formatters conflict:

  • ❌ EssentialsChat + VentureChat + HeroChat
  • ✅ Pick ONE chat plugin

World Editors

Section titled “World Editors”

Large operations can conflict:

  • ❌ WorldEdit + FAWE running same operation
  • ✅ Use one, disable the other

Version Compatibility Check

Section titled “Version Compatibility Check”

Before installing any plugin:

  1. Check the plugin page for supported versions
  2. Match your server version (e.g., 1.20.4)
  3. Check API version (Bukkit, Spigot, Paper)
  4. Download the correct file for your version

Common Version Errors

Section titled “Common Version Errors”
ErrorFix
Unsupported API versionPlugin too new/old for server
Plugin was built for 1.19Download correct version
Missing API: PaperPlugin requires Paper, not Spigot

Forge/Fabric Mod Conflicts

Section titled “Forge/Fabric Mod Conflicts”

Common Issues

Section titled “Common Issues”
  • Duplicate functionality — Two mods adding same items/blocks
  • Mixins conflicts — Mods modifying same game code
  • Load order — Some mods must load before others

Mod-Specific Logs

Section titled “Mod-Specific Logs”
  • Forge: Check logs/debug.log and crash-reports/
  • Fabric: Check logs/latest.log and crash reports

Fabric-Specific

Section titled “Fabric-Specific”

Fabric mods often have “dependencies” listed:

  • Requires: fabric-api >= 0.90
  • Make sure you have Fabric API installed

After Finding the Problem

Section titled “After Finding the Problem”

Option 1: Remove It

Section titled “Option 1: Remove It”

If you don’t need the plugin/mod, just delete it.

Option 2: Find Alternative

Section titled “Option 2: Find Alternative”

Search for a different plugin that does the same thing but works.

Option 3: Report the Bug

Section titled “Option 3: Report the Bug”

If it’s a plugin bug:

  1. Go to the plugin’s page (Spigot, Modrinth, CurseForge)
  2. Check for existing bug reports
  3. Report with your error log if new

Option 4: Downgrade

Section titled “Option 4: Downgrade”

Sometimes newer versions break things. Try an older version.

Still Not Working?

Section titled “Still Not Working?”

Before contacting support, gather these 3 things:

  1. Server ID — found in your panel URL or dashboard
  2. What you tried — list the steps you already attempted
  3. Error message or screenshot — exact text or image of what you see

Then contact us: