> ## Documentation Index
> Fetch the complete documentation index at: https://docs.purpify.host/llms.txt
> Use this file to discover all available pages before exploring further.

# Install Java mods and modpacks

> Install Minecraft Java mods and modpacks with Purpify's installers or upload mod files manually.

Use Purpify's modpack installer or mod installer when the content is available there. For a manual installation, upload compatible mod files to `/mods`.

## Before you install mods

The server and players must use compatible combinations of:

* Minecraft version
* Mod loader
* Mod or modpack version
* Required dependencies

Create a backup before installing or updating mods.

## Install a modpack

<Steps>
  <Step title="Open the modpack installer">
    Manage the Java server in the [game panel](https://panel.purpify.host), then open Purpify's modpack installer.
  </Step>

  <Step title="Choose the modpack release">
    Select a release compatible with the Minecraft version and loader you want to use.
  </Step>

  <Step title="Install the modpack">
    Start the installation and wait until the panel reports that it finished.
  </Step>

  <Step title="Start and verify">
    Start the server, watch the console, and connect with the matching client-side modpack.
  </Step>
</Steps>

## Install an individual mod

Use Purpify's mod installer to find and install a compatible mod. Check whether the mod also needs to be installed on each player's client.

## Install a mod manually

<Steps>
  <Step title="Check compatibility">
    Confirm the mod supports the server's Minecraft version and mod loader. Download every required dependency.
  </Step>

  <Step title="Stop the server">
    Stop the server before changing mod files.
  </Step>

  <Step title="Upload the mod">
    Upload the mod and its dependencies to the `/mods` folder.
  </Step>

  <Step title="Start and verify">
    Start the server and check the console for missing dependency, wrong loader, or version errors.
  </Step>
</Steps>

## Diagnose a mod crash

Start with the server console, latest log, and crash report. The most useful error often appears before the final line that says the server stopped.

You can give the relevant error log to an AI assistant such as ChatGPT and ask it to identify:

* The mod named in the first relevant error
* A missing dependency
* A Minecraft or mod-loader version mismatch
* Conflicting mods
* The next safe test to perform

<Warning>
  Remove passwords, access tokens, private server addresses, player information, and unrelated log history before sharing logs with an AI service. Treat the AI response as a diagnostic suggestion and verify it before deleting files or changing versions.
</Warning>

Example prompt:

```text theme={"dark"}
This Minecraft Java server crashes during startup.
Identify the first relevant error, the mod or dependency involved,
and the safest next troubleshooting step.

Minecraft version: <version>
Mod loader and version: <loader>
Last change: <mod or modpack change>
Relevant error log:
<paste the redacted error and several lines before it>
```

If the error names Forge, NeoForge, Fabric, Quilt, a loader version, or an incompatible mod list, follow [Troubleshoot Java mod-loader mismatches](/troubleshooting/mod-loader-errors).