Vault est bien installé mais je vais regarder pour les logs .
[17:21:02] [Server thread/ERROR]: Error occurred while enabling Quests v2.0.0 (Is it up to date?)
java.lang.NoSuchMethodError: org.bukkit.configuration.file.FileConfiguration.load(Ljava/io/InputStream

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at me.blackvein.quests.Quests.defaultConfigFile(Quests.java:311) ~[?:?]
at me.blackvein.quests.Quests.onEnable(Quests.java:191) ~[?:?]
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:264) ~[spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:337) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:403) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:381) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:330) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.reload(CraftServer.java:752) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.Bukkit.reload(Bukkit.java:525) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:27) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at org.bukkit.craftbukkit.v1_12_R1.CraftServer.dispatchCommand(CraftServer.java:648) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.PlayerConnection.handleCommand(PlayerConnection.java:1397) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.PlayerConnection.a(PlayerConnection.java:1232) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:45) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.PacketPlayInChat.a(PacketPlayInChat.java:1) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_72]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_72]
at net.minecraft.server.v1_12_R1.SystemUtils.a(SourceFile:46) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:748) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:406) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:679) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:577) [spigot-1.12.2.jar:git-Spigot-109b080-4119224]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_72]