# A plugin works better with a plugin that is not installed

A plugin started without an optional plugin it recommends, so some of its features stay off until that plugin is added.

- Code: `plugin_optional_dependency_missing`
- Severity: warning
- Category: Plugins
- Server types: Paper, Spigot
- Page: https://failures.perland.online/failures/plugin_optional_dependency_missing/

## Example log

```text
[10:02:17 INFO]: [Essentials] Enabling Essentials v2.21.0
[10:02:18 WARN]: [Essentials] Detected supported permissions plugin LuckPerms without Vault installed.
[10:02:18 WARN]: [Essentials] Features such as chat prefixes/suffixes and group-related functionality will not work until you install Vault.
```

## Parameters

| Parameter | Meaning |
| --- | --- |
| `dependency` | The plugin it recommends installing, such as `Vault`. |

## Log lines this page covers

- `Detected supported permissions plugin ... without ... installed.`
- `Features such as ... will not work until you install ...`

## What it means

Some plugins have optional dependencies: they start without them but turn some features off. This issue is a plugin telling you which one it is missing. The diagnosis reads the wording EssentialsX uses when it finds a permissions plugin such as LuckPerms but no Vault, the bridge plugin it reads group prefixes, suffixes and group data through.

Nothing failed. The plugin runs, and only the features it names do not work: in the EssentialsX case, chat prefixes and suffixes and anything based on a player's group. EssentialsX prints two lines about it, which count as one issue.

## Why it happens

- **The bridge plugin was never installed.** Vault is a separate download; EssentialsX and LuckPerms do not include it.
- **It was removed or failed to load.** Look for a load error about Vault earlier in the same log.

## How to fix

1. Decide whether you need the features the warning names. If you do not use chat prefixes or group-based features, you can leave this warning.
2. Otherwise download the plugin it names (for this case, Vault) from its official page and put the jar in the `plugins` folder.
3. Restart the server. The warning should be gone, and EssentialsX should report that it uses your permissions plugin with Vault.

## In Perland

The issue appears in the server's Diagnosis tab as a warning naming the plugin to install. You can add that plugin with Plugin Studio, or upload its jar to the `plugins` folder in the Files tab, then restart the server.

## References

- [EssentialsX](https://essentialsx.net/)
- [Vault on SpigotMC](https://www.spigotmc.org/resources/vault.34315/)