error log for groupmanager

2017-07-24 22-18
=============================== GM ERROR LOG ===============================
= ERROR REPORT START - 2.0.1-b332 =

java.lang.IllegalArgumentException: You have no groups in plugins/GroupManager/worlds/world/groups.yml.
 at org.anjocaido.groupmanager.dataholder.WorldDataHolder.loadGroups(WorldDataHolder.java:611)
 at org.anjocaido.groupmanager.dataholder.WorldDataHolder.loadGroups(WorldDataHolder.java:509)
 at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.loadWorld(WorldsHolder.java:694)
 at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.loadWorld(WorldsHolder.java:656)
 at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.initialWorldLoading(WorldsHolder.java:105)
 at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.initialLoad(WorldsHolder.java:95)
 at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.resetWorldsHolder(WorldsHolder.java:86)
 at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.<init>(WorldsHolder.java:53)
 at org.anjocaido.groupmanager.GroupManager.onEnable(GroupManager.java:176)
 at org.anjocaido.groupmanager.GroupManager.onEnable(GroupManager.java:99)
 at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:264)
 at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:337)
 at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:402)
 at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:377)
 at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:327)
 at net.minecraft.server.v1_12_R1.MinecraftServer.t(MinecraftServer.java:421)
 at net.minecraft.server.v1_12_R1.MinecraftServer.l(MinecraftServer.java:382)
 at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:337)
 at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:272)
 at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:544)
 at java.lang.Thread.run(Thread.java:748)

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