Solving Mod and Plugin Conflicts

So your server is crashing on startup or a specific command just stopped working? It’s usually an "addon cage match" where two mods or plugins are trying to do the same thing at the same time and crashing the server in the process. Here’s how to find the winner.

1. Let the Logs Tell the Story

The answer is almost always hiding in your Console or the logs/latest.log file. Don't let the technical jargon scare you; just scan for these keywords:

CRITICAL: Something broke so badly the server gave up.
INCOMPATIBLE: Two mods are literally telling the server they can't work together.
MOD_NOT_FOUND: You installed a mod but forgot its "library" (the extra file it needs to run).

2. The "Binary Search": A Pro's Secret

If the logs are a mess and you have 50+ mods, don't delete them one by one. Use the "50/50 method":

Save a Snapshot: Always take a Snapshot first so you don't lose anything.
Disable Half: Turn off half of your addons in the Plugins or Mods tab.
Check:
- If the server starts, the "bad" mod is in the half you disabled.
- If it still crashes, the "bad" mod is in the half that is still on.
Repeat: Half the list again and again. You can find one single broken mod out of 128 in just 7 restarts.

3. Quick Fixes That Often Work

Update Everything: 90% of conflicts are fixed in newer versions. If a plugin is crashing, check for an update!
Library Check: Did you miss a required mod? Many Fabric/Forge mods need things like CreativeCore or ClothConfig to work.
The "Reset" Trick: Sometimes a config file gets corrupted. Try renaming the folder for the failing plugin (e.g., LuckPerms_OLD) and let the server generate a fresh one.

4. Know Your Limits

Mixing different types of software is the fastest way to get a crash:

Paper/Spigot: Usually very stable.
Fabric/Forge: Pretty good, but version matches are critical.
"Hybrid" Servers (Arclight, Mohist): These try to run both Mods and Plugins at once. They are famously buggy and prone to conflicts. Avoid these unless you're an expert.

Still stuck in a crash loop? Join our Discord and share your logs. Our staff has seen every error message imaginable.