My Error File

2015-04-19 14-48
=============================== GM ERROR LOG ===============================
= ERROR REPORT START - 2.1.31 (Phoenix) =

java.lang.IllegalArgumentException: The following file couldn't pass on Parser.
plugins\GroupManager\worlds\world\groups.yml
	at org.anjocaido.groupmanager.dataholder.WorldDataHolder.loadGroups(WorldDataHolder.java:590)
	at org.anjocaido.groupmanager.dataholder.WorldDataHolder.loadGroups(WorldDataHolder.java:510)
	at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.loadWorld(WorldsHolder.java:678)
	at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.loadWorld(WorldsHolder.java:640)
	at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.initialWorldLoading(WorldsHolder.java:110)
	at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.initialLoad(WorldsHolder.java:100)
	at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.resetWorldsHolder(WorldsHolder.java:92)
	at org.anjocaido.groupmanager.dataholder.worlds.WorldsHolder.<init>(WorldsHolder.java:59)
	at org.anjocaido.groupmanager.GroupManager.onEnable(GroupManager.java:179)
	at org.anjocaido.groupmanager.GroupManager.onEnable(GroupManager.java:103)
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:316)
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:368)
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:410)
	at org.bukkit.craftbukkit.v1_7_R4.CraftServer.loadPlugin(CraftServer.java:415)
	at org.bukkit.craftbukkit.v1_7_R4.CraftServer.enablePlugins(CraftServer.java:349)
	at net.minecraft.server.MinecraftServer.func_71243_i(MinecraftServer.java:500)
	at net.minecraft.server.MinecraftServer.func_71222_d(MinecraftServer.java:474)
	at net.minecraft.server.MinecraftServer.func_71247_a(MinecraftServer.java:434)
	at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:329)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:620)
	at java.lang.Thread.run(Unknown Source)
Caused by: while scanning for the next token
found character 	'\t' that cannot start any token
 in "<reader>", line 152, column 28:
        - essentials.kit.rookie
                               ^

	at org.yaml.snakeyaml.scanner.ScannerImpl.fetchMoreTokens(ScannerImpl.java:358)
	at org.yaml.snakeyaml.scanner.ScannerImpl.checkToken(ScannerImpl.java:179)
	at org.yaml.snakeyaml.parser.ParserImpl$ParseIndentlessSequenceEntry.produce(ParserImpl.java:537)
	at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:161)
	at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:146)
	at org.yaml.snakeyaml.composer.Composer.composeSequenceNode(Composer.java:203)
	at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:158)
	at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:237)
	at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:160)
	at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:237)
	at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:160)
	at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:237)
	at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:160)
	at org.yaml.snakeyaml.composer.Composer.composeDocument(Composer.java:123)
	at org.yaml.snakeyaml.composer.Composer.getSingleNode(Composer.java:106)
	at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:121)
	at org.yaml.snakeyaml.Yaml.loadFromReader(Yaml.java:480)
	at org.yaml.snakeyaml.Yaml.load(Yaml.java:423)
	at org.anjocaido.groupmanager.dataholder.WorldDataHolder.loadGroups(WorldDataHolder.java:585)
	... 20 more