faq installation errors

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🛠️ FAQ: Installation and Startup Errors

1. [Vault] ERROR: Could not register Economy — another plugin already did it

Another plugin has already registered the net.milkbowl.vault.economy.Economy interface.

Typical causes:

• You have classic Vault.jar + EssentialsX Economy.jar (Essentials also registers Economy)
• You have an old economy plugin (CMI, Gringotts, etc.)

Solution:

1. Choose only one economy plugin: if you are going to use Vault 2.1, remove the EssentialsX Economy jar and/or the old Vault.jar.
2. Or the other way around: if you need EssentialsX Economy, remove vault-2.x.x.jar.
3. Restart the server.

2. HikariPool-1 - Exception during pool initialization (MySQL)

Database cannot connect to the HikariCP pool.

Steps to check:

storage:
  use_mysql: true
  mysql:
    host: 127.0.0.1      # Make sure it's not localhost if you use socket
    port: 3306
    database: vault      # Does the DB exist? Run CREATE DATABASE vault;
    username: vaultuser
    password: "correct"  # Double quotes if it has special characters

Check order:

1. Open a shell and test: mysql -h127.0.0.1 -uvaultuser -p vault -e "SELECT 1"
2. Verify useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true in params: if you use MySQL 8.
3. Make sure the pool is not exhausted (pool_size: 10 by default; don't raise it unnecessarily).
4. Look at the stacktrace: if it says Communications link failure it's network/firewall; if Access denied it's credentials.

3. NoSuchMethodError: PlayerProfile / SkinsRestorer

The head in /pay does not render.

Causes:

• You are on Spigot 1.12 or earlier without SkinsRestorer.
• The applyLivePlayerProfile / applySkinRestorerSkin reflection cannot find the API.

Solution:

• Install SkinsRestorer (the plugin tries to load net.skinsrestorer.api.SkinsRestorerProvider dynamically).
• Make sure softdepend: [SkinsRestorer] is loaded earlier in the startup order.

4. UnsupportedClassVersionError on load

You are using a Java version older than the one the JAR was compiled for.

JAR	Minimum Java
vault-2.1.0-java17.jar	Java 17
vault-2.1.0-java21.jar	Java 21

Check with java -version. If your panel/host only provides Java 16 or lower, update the server runtime.

5. Messages appear as pay.only_players (not translated)

Messages did not find the language file.

Solution:

1. Confirm that plugins/Vault/messages/messages_en.yml (or the corresponding one) exists and is not corrupted. If you deleted it by accident, reinstall the JAR so they are generated again.
2. In config.yml check language: en (must be one of: en, es, fr, de, nl, pl, pt, ru, zh_CN, zh_TW, hi).
3. Run /vault reload. If it still fails, delete the messages/ folder and let the plugin regenerate it.

6. WARN: Failed to create transactions JSON log

Failed to create logs/daily-YYYY-MM-DD.json.

Common cause: write permissions of the Windows/Linux user over plugins/Vault/.

Solution:

• On Linux: chown -R minecraft:minecraft plugins/Vault and chmod -R u+rwX plugins/Vault
• On Windows: right-click → Properties → Security → Ensure the server user has "Write" permission
• The daily log is not mandatory for operation; without it you still have FileTxDAO/MySqlTxDAO.