[GEN/SEC/ECON/TP/ADMN] Essentials 2.9.1 - A collection of useful commands [1.2.4, 1.2.5-R1]

Essentials 2.9.1 - A collection of useful commands and features

Essentials offers over 100 commands that are useful on just about every server. Inside you will find commands to help both players and staff.
Features include: TP, warps, homes, kits, mob spawning, and various mod tools.


The last 3 major releases of Essentials have contained over 1000 commits, and complete rewrites to major sections of the code. With 2.7 we focused on reducing 'bloat', and with 2.8 we focused on improving performance, and with 2.9 we somehow managed to reduce CPU usage again! If you download Essentials today, you will find it to be faster and smoother yet again. Now supporting Minecraft 1.2, it's our best release yet.

• Essentials Core Download
• Essentials Extras Download
• Group Manager Download
• (Clear your browser cache if you get 2.8.4)
• Download Mirror

• Dev builds / Bleeding-edge builds
• Feature requests, Suggestions and Issues
• Live Chat - Come here for help first
• GitHub
• Changelog
• Install Guide
• Command Reference, click command to expand info.
• Command Permissions.
• Donate
• Essentials @ BukkitDev

• CraftBukkit version 1000-1060 (Minecraft 1.7.3), use Essentials 2.5
• CraftBukkit version 1185-1337 (Minecraft 1.8), use Essentials 2.6
• CraftBukkit version 1597 (Minecraft 1.0), use Essentials 2.7
• CraftBukkit version 1846+ (Minecraft 1.1), use Essentials 2.8
• CraftBukkit version 2122+ (Minecraft 1.2), use Essentials 2.9

Please don't post your problems or feature suggestions here - we can't keep track of them, and we will most likely not respond. Talk to us live in #essentials via irc.esper.net, or file a support ticket on Assembla. You don't have to register there.


How to get Help << click me

Plugin Conflicts

• bColoredChat: The signs code conflicts with our signs code. Users can create valid signs, even if they don't have the permission in essentials. Use essentials.signs.color permission for colored signs and not the one from this plugin.

Version Notes:

• 3.x (upcoming)
  • There will be some changes on how we save the config.yml. We will support automatic update after a new version, so that you always have the newest options in there.
  • There will be a new installer and updater for Essentials.
  • Warning for developers: If you build against Essentials, there will be breaking changes with the next big release. The EssentialsEco api will not break, but eventually be deprecated.
• 2.9.1
  • Minecraft 1.2/Craftbukkit 1.2.4-R1 / 1.2.5-R1
  • New mob/entity support
  • Adding permissions for overwriting exisitng warps
    • essentials.warp.overwrite.[warpname] will allow overwriting of existing warps
    • essentials.warp.overwrite.* for all warps
  • Fix UTF8 handling in Configuration class, all files are now UTF8 again
  • Added PluginMetricsby Hidendra, can be disabled by /essentials opt-out.
    • Warns on first start and first staff join and has 5 minute warning before logging starts.
  • Speed improvements
  • New help formatting and cleanup.
  • Adding option to modify all users balances (including offline) /eco reset ** <amount>
  • Allow more currency customization. Added currency key to messages.
  • Adding starter/newbie kit to EssentialsSpawn
  • Several fixes for changes in Bukkit
  • Add ban reason to /seen
  • Update setworth to allow /setworth <price> ingame
  • Allow /setworth to be used from console.
  • Adding jail status to /whois.
  • New permission: essentials.tp.others - Allows players to /tp <p1> <p2> replaces old reused permission.
  • New permission usage: if world-teleport-permissions is true in the config, TP commands will now check for essentials.world.<worldname> when a tp would switch worlds.
  • Add 'color' sign type to config file. Enforce colour permission on signs when essentials signs are enabled.
  • New permission: essentials.chat.url Without this perm, URLs will be modified not to be links.
  • New permission: essentials.msg.url Without this perm, URLs in private messages will be modified not to be links.
  • New command: /fly New permissions: essentials.fly, essentials.fly.others
  • Improve kit matching, and add enchantments. Enchanted kit example in config.yml
  • Disabling player list updates by default (can mess with tab completion in chat) (configurable in config.yml)
  • Invsee now shows a live player inventory in a window, rather than cloning players inventory.
  • New Permission: essentials.invsee.modify - Player with this permission will be able to add/remove items from the other players inventory.
  • Update [balance] sign to use currency formatting.
  • Update tp to check if target player has tptoggle disabled.
  • Update tpo to allow player to player tp.
  • Adding world permission checks to: tpaall tpall tpahere tphere tpohe.re
  • 3 more bundled local translations: cs it and pt
  • Can now use backup feature to force world saves, if not used to trigger backup scripts.
  • New mob options including villager types, ocelots (and trained cats).
  • Tree commands can now spawn all tree types
  • New colour perms:
    • essentials.chat.color - This allows you to color your chat messages using color codes.
    • essentials.chat.magic - This allows you to use the matrix/magic color in your chat messages.
    • essentials.chat.format - This allows you to format your chat messages using format codes.
    • essentials.msg.color - This allows you to color your private messages using color codes.
    • essentials.msg.magic - This allows you to use the matrix/magic color in your private messages.
    • essentials.msg.format - This allows you to format your private messages using format codes.
    • essentials.signs.color - This allows you to color your signs using color codes.
    • essentials.signs.magic - This allows you to use the matrix/magic color in your signs
    • essentials.signs.format - This allows you to format your signs using format codes.
    • essentials.nick.color - This allows you to color your nick using color codes.
    • essentials.nick.magic - This allows you to use the matrix/magic color in your nick
    • essentials.nick.format - This allows you to format your nick using format codes.
  • User is required to have the permission for the world he is in, before he can teleport users outside this world, to it.
• 2.8.4
  • CraftBukkit 1.1-R7
  • New starter kit
  • Adjust op prefixes
  • Performance improvements
  • Allow colours in group tags
  • Currency formatting can be edited in messages file
• 2.8.3
  • CraftBukkit 1.1-R6 / 1988
  • New event system
  • Min money config option
  • Jail respawn fix
  • Powertool optimisation, and abuse reduction.
  • BPerms api fix.
  • Extra tpaccept perm check, for better multiworld support
  • New perm: essentials.sudo.exempt
  • Disposal sign disabled due to bukkit bug.
  • Group Manager bug fixes
• 2.8.2
  • CraftBukkit 1846
  • Colour related bug fixes
  • Item blacklist warning fix
  • Item repair, wont repair potions/dyes
  • Better handle file corruption, and jail errors.
• 2.8.1 / MC 1.1
  • Update for MC 1.1 / CraftBukkit 1.1 / 1818,1840
  • Prevent that the pay command sends money to all player, if the playername is empty
  • Added the new Enchantments
  • Added the new eggs to items.csv, it should update automatically, if you have not modified it
  • Adjusted new player spawn behaviour
  • Fixed {WorldDate}
  • Fixed double charges on /home
  • Fixed problem with spawns and jails in worlds that are loaded after Essentials
  • Optimized event handling
  • Strip colors from chat messages, if the user does not have the permission essentials.chat.color
  • Updated to use the new bukkit event system
  • Added support for Vault
  • Added new permission essentials.protect.alerts.notrigger
  • Updated French translation by Léa Gris
  • Home/Bed behaviour was modified to give higher priority to beds when spawning.
  • Bed home will no longer be listed if it doesn't exist
  • Signs are now optional and disabled by default
  • Performance tuning of the core and chat.
  • New GroupManager 1.9
  
  

  • • Added custom events so plugins can now be notified of changes within GroupManager.
    • GM now registers with Bukkits ServicesManager.
    • Deleting the contents of GlobalGroups.yml will no longer thrown a NullPointerException.
    • Removed op permissions from admins in the default GloblaGroups.yml.
    • Changed ServicesManager registration to lowest from normal.
    • Fixed 'manucheckp' returning a null for the searched node when it's a group/subgroup.
    • manpromote and mandemote now correctly send the notification to the console if the command was issued there.
    • Expanded GlobalGroups.yml and Groups.yml to include Towny permissions.
    • Delayed GroupManager events so Superperms will be fully updated before plugins receive the events.
    • Changed the way events are raised to prevent variable corruption.
    • Reload GlobalGroups when you perform a world load.
    • Changed GlobalGroups to save/load before local groups in the scheduled data saving/loading
    • Fix 'manucheckp' to correctly report if a permission is available from GroupManager or Bukkit.
    • Changed over to a reflection method for populating superperms as Bukkit lags when you handle permissions one at a time.
    • Major, MAJOR changes to support partial/full world mirroring.
    • You can now mirror groups.yml, users.yml or both files between different worlds.
    • Catch NullPointerErrors generated by blank permission nodes.
    • Removed '- bukkit.command' form the globalgroups permission nodes.
    • Optimize populating Bukkit perms so we no longer calculate the child nodes (Bukkit already does this).
    • Added a tidy error message for invalid permission entries in GlobalGroups.
    • Better optimize assembling of a players permissions and allow the * node to populate all registered superperms.
    • Fixed text when adding a subgroup to not say the player was moved.
    • Update to new Bukkit Event system.
    • Update GroupManagerBridge for new event system.
    • Fixed a random null error upon a player portaling.
    • Fixed infinite loop error on player join.
    • Optimized code to only update the player logging in instead of all players online.
    • Added recursive loop detection for World mirroring (you may not set the main world as a mirror of another).
    • Fixed fetching world data so it no longer returns the mirrored world for groups. Each world data holder now points to the correct data set, so can be returned as an object.
    • Changed addSubGroup() to only add the group if it doesn't already exist (no need to update an already existing group).
    • addSubGroup now returns a boolean for success/failure.
    • '/manuaddsub' now correctly reports if it was able to add the sub group.
    • Allow negation to the * permission node when populating superperms.
    • Fix trying to modify an unmodifiable collection breaking superperms.
    • Fixed subgroups (I broke earlier).
    • Check for a null player object in the PlayerTeleportEvent.
    • Trap errors in fetching the mirrors map.
    • Fixed an infinite loop error when using '/manudel' on a logged in player. It caused setDefaultGroup to trigger a bukkit update when no GM User existed yet.

... older change logs can be found at BukkitDev.

Over 1.000.000 downloads since May 2011!

Join the team
There are many features to be added to Essentials, so we are looking for new developers to help us out. You should have at least some java skills. Contact snowleo or KHobbits on irc if you want to join.

If you only want to add code to Essentials, create a pull request at GitHub.

We are also looking for translation of our messages file. Translate it to your language and send it to us. Native speakers preferred. Only use these characters when translating the files. Otherwise, the message will be broken in game.

General information
We have rolling releases, the second number in our version number changes, if there is a new minecraft or major bukkit update. We only support the recommended versions of Bukkit.

If you have problems, check if you have the newest versions of Bukkit and Essentials first. In many cases the problem has already been fixed.

Essentials is split in several jar files. These are modules that can be removed, if you don't need them:
Modules that need Essentials.jar: EssentialsChat, EssentialsProtect, EssentialsSpawn, EssentialsGeoIP, EssentialsXMPP

Standalone modules: EssentialsGroupBridge (FakePermission) in combination with EssentialsGroupManager (GroupManager formerly developed by AnjoCaido).

Essentials is maintained by KHobbits and snowleo. Group Manager is maintained by ElgarL.

Contributions in the past by Zenexer, Aelux, Brettflan, KimKandor, ceulemans, necrodoom, ementalo, okamosy, khyperia and others. Check the commit list at github for all names.

Our repository is now at github. Pull requests can be done there.

Essentials is licensed under GPLv3.

Follow us on Twitter
You can get instant notification when we make updates by subscribing to our automated Twitter feed. Just follow @EssentialsTeam.

Donations
Essentials development is handled by a rolling team of developers who give up their free time to help you maintain your servers. The team accepts donations which will be split between the active team members.

We would like to offer a thanks to the following donators who have contributed above the average and have made a significant contribution to the project.

• Andrewkm - Server owner, Ecocitycraft.com
• Stickmenz - Server owner, RealmCraft
• X-Rob - Server owner, Minecraft Australia
• Iaccidentally - Essentials helper
• Hvarr - Server Owner, Legendary Island of the Lost Treasures

If your server generates a profit or you are hosting company, we would really appreciate if you donate to this project. Please, donate!


Learn by example
@Samkio and xTorrent made a great YouTube video explaining what Essentials is, its different parts, and how to install it. Watch it on YouTube.

@BrandonHopkins made a video about GroupManager and how to set it up for the first time.

Other Highly Recommended Plugins
We and many other server owners use these plugins in conjunction with Essentials:

• WorldEdit <3
• WorldGuard (Slightly more advanced replacement for EssentialsProtect)
• HeroChat
• CraftIRC <3
• PortalStick <3 <3
• VanishNoPacket

Please don't post your problems or feature suggestions here - we can't keep track of them, and we will most likely not respond. Talk to us live in #essentials via irc.esper.net, or file a support ticket on Assembla. You don't have to register there.

Used it for a while, great stuff!

Essentials is really quite useful. Personally I recommend that most people running a minecraft server start off with essentials and expand out from there.

If someone has a need for more specialised commands, recent versions of essentials will give priority to other plugins with that use the same commands. This means you can override any commands or functionality you don't need with more specialised plugins.

I suggest that users don't rely on getting answers from this thread, because essentials support is focused on IRC help.

awesome plugin. recommended for people who are new in server mananging.

Code:

20:00:18 [SEVERE] java.lang.NoSuchMethodError: com.earth2me.essentials.Essentials.loadClasses()V
20:00:18 [SEVERE]       at com.earth2me.essentials.chat.EssentialsChatPlayerListener.onPlayerChat(EssentialsChatPlayerListener.java:56)
20:00:18 [SEVERE]       at org.bukkit.plugin.java.JavaPluginLoader$6.execute(JavaPluginLoader.java:236)
20:00:18 [SEVERE]       at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:59)
20:00:18 [SEVERE]       at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:257)
20:00:18 [SEVERE]       at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:646)
20:00:18 [SEVERE]       at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:634)
20:00:18 [SEVERE]       at net.minecraft.server.Packet3Chat.a(Packet3Chat.java:32)
20:00:18 [SEVERE]       at net.minecraft.server.NetworkManager.a(NetworkManager.java:195)
20:00:18 [SEVERE]       at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:74)
20:00:18 [SEVERE]       at net.minecraft.server.NetworkListenThread.a(SourceFile:100)
20:00:18 [SEVERE]       at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:370)
20:00:18 [SEVERE]       at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:285)
20:00:18 [SEVERE]       at net.minecraft.server.ThreadServerApplication.run(SourceFile:394)

WHY?
essentials 2.2 (without protect and chat)
bukkit 740
linux ubuntu
shitload of pluins (MinecartMania, uQuest, cmMMO, HeroBounty, dynmap, worldedit, worldguard, ichat, jail, iconomy, chestshop, multiverse, multiinv, bukkituptodate, lwc, borderguard, bigbrother, authme, nocheat, slowhealth)

sauevaem: list exact essentials version. also post server.log.

also more details about error.

Remove EssentialsChat.jar from your plugins folder.

Great plugin, I have to say. Really apreciate that you guys keep developing groupmanager, even as anjo left for a while. For me its the best permission manager ever created

EDIT:
Also, why the thread change?

I was going to argue with you that there is no chat plugin in my folder, but when I checked it turned out that there actually is... thanks

We changed the thread, because Zenexer is busy on other projects and didn't update the original thread.

1) Is there a way to set an additional spawn for people that have not joined the server before?
2) People without the essentials.plugin node can use /plugins, which apparently functions as /plugin list. Can this be fixed? I'm not interested in players being able to see what plugins are running on my server.

1- yes, "/setspawn newbies" - but the name can be changed on the config files

1) As anon said.
2) The command /plugins belongs to bukkit. It's not part of Essentials

Wow, new page. Great news. Keep up the great work guys. Love the plugin.

new thread, same ones and twos:

1st: love your plugin!
2nd: is it possible to disable "mail"-system so we won't see the "You have blabla new mail" on startup?
it's kinda cool but we don't need this awesome feature and I haven't found some options for that issue in the config files

thx a lot

Both thanks for replying!

In config:
disabled-commands: mail

Thanks a lot, Essentials #1 plugin.

cool! thanx! dunno why I didn't recognize this!

have fun & enjoy

When someone on my server types /who, they get an error message which just says:

Error: d

Any suggestions as to how I can fix this?
Using this version, 2.2

Weird, I'm unable to use Essential core commands like /list. My Permissions config haven't changed for the last few hundred Bukkit builds, I have myself enabled to use every command and yet /list yields no output at all. Just a message on the console saying "Player tried to use command: /list". Anyone else with issues in the latest Bukkit builds & Essentials? Running Craftbukkit #735 + Essentials 2.2

EDIT: Ignore this post. Essentials didn't load 'cause I had an error in my permissions config as well as my Essentials config. Everything's working fine.

I got this error, I've tried many thing to fix it, no luck. Anyone can help?

2011-05-01 02:02:29 [SEVERE] special characters are not allowed loading EssentialsSpawn v2.2.7 (Is it up to date?)
unacceptable character #0 special characters are not allowed
in "<reader>", position 0
at org.yaml.snakeyaml.reader.StreamReader.checkPrintable(StreamReader.java:68)
at org.yaml.snakeyaml.reader.StreamReader.update(StreamReader.java:159)
at org.yaml.snakeyaml.reader.StreamReader.peek(StreamReader.java:117)
at org.yaml.snakeyaml.reader.StreamReader.peek(StreamReader.java:106)
at org.yaml.snakeyaml.scanner.ScannerImpl.scanToNextToken(ScannerImpl.java:964)
at org.yaml.snakeyaml.scanner.ScannerImpl.fetchMoreTokens(ScannerImpl.java:237)
at org.yaml.snakeyaml.scanner.ScannerImpl.checkToken(ScannerImpl.java:183)
at org.yaml.snakeyaml.parser.ParserImpl$ParseImplicitDocumentStart.produce(ParserImpl.java:200)
at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:163)
at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:148)
at org.yaml.snakeyaml.composer.Composer.getSingleNode(Composer.java:104)
at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:124)
at org.yaml.snakeyaml.Yaml.load(Yaml.java:264)
at org.bukkit.util.config.Configuration.load(Configuration.java:73)
at com.earth2me.essentials.EssentialsConf.load(EssentialsConf.java:64)
at com.earth2me.essentials.Warps.reloadConfig(Warps.java:210)
at com.earth2me.essentials.Warps.<init>(Warps.java:32)
at com.earth2me.essentials.Essentials.onEnable(Essentials.java:104)
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:127)
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:632)
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:218)
at com.earth2me.essentials.spawn.EssentialsSpawn.onEnable(EssentialsSpawn.java:29)
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:127)
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:632)
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:218)
at org.bukkit.craftbukkit.CraftServer.loadPlugin(CraftServer.java:116)
at org.bukkit.craftbukkit.CraftServer.loadPlugins(CraftServer.java:94)
at net.minecraft.server.MinecraftServer.e(MinecraftServer.java:217)
at net.minecraft.server.MinecraftServer.a(MinecraftServer.java:204)
at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:144)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:259)
at net.minecraft.server.ThreadServerApplication.run(SourceFile:394)

I have a question.

I am trying to use the command /world (name of world) and its not working, only when I type /world 0 it respawns me at the spawnpoint of the current world I am in.



I have other maps in the server folder but I see this message above. Do I need to add the map names in a config file somewhere?

eagle

IRC offers no help, nobody talks. /who, /list, etc causes this error:

Code:

01:51:21 [SEVERE] null
org.bukkit.command.CommandException: Unhandled exception executing command 'who' in plugin Essentials v2.2.7
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:37)
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:85)
        at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:255)
        at net.minecraft.server.NetServerHandler.handleCommand(NetServerHandler.java:675)
        at net.minecraft.server.NetServerHandler.chat(NetServerHandler.java:638)
        at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:632)
        at net.minecraft.server.Packet3Chat.a(Packet3Chat.java:32)
        at net.minecraft.server.NetworkManager.a(NetworkManager.java:195)
        at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:74)
        at net.minecraft.server.NetworkListenThread.a(SourceFile:100)
        at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:370)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:285)
        at net.minecraft.server.ThreadServerApplication.run(SourceFile:394)
Caused by: org.bukkit.command.CommandException: Unhandled exception executing command 'who' in plugin SpyerAdmin v1.0
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:37)
        at com.earth2me.essentials.Essentials.onCommand(Essentials.java:524)
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:35)
        ... 12 more
Caused by: java.lang.NullPointerException
        at nickguletskii200.SpyerAdmin.SpyerAdmin.onCommand(Unknown Source)
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:35)
        ... 14 more
>

B740

Weather is working good except in snowy areas nothing happens

@essentialsteam

The warp, spawn and home commands seem to be offset again, as in I will set them on one block and when I use the commands, I will be warped a little forward of where I set it or to the side a bit.

@Dig1tal: Set debug: true in config.yml and report the error that will be in console.

@ambientmf: Any errors on server start?

@Suprem20: One of your warps seems to be broken, check the .yml files in warps folder.

@eagleFMJ: You need a plugin like Multiverse.

@Platypus: SpyerAdmin is creating that error, maybe update?

@SpyDaniel: What is the offset? (Press the F3 key to show your position)

@essentialsteam
Thats weird, the coroods are the same, but the offset is deffenntly happening. If I stand in the middle of 4 blocks, so I'm right on the + of the 4 and set a warp and then use that warp, I will be warped to the top right of the four blocks.

Also, the essentials config, for MoTD, colours do not seem to work with it. Using EssentialsChat. But colours do work in chat :\ - Never mind, was using ^ instead of & for the config.

Code:

16:47:49 [SEVERE] Could not pass event PLAYER_QUIT to TrainYourLung
java.lang.NullPointerException
        at bukkit.Sixael.TrainYourLung.TYLPlayerListener.onPlayerQuit(TYLPlayerListener.java:39)
        at org.bukkit.plugin.java.JavaPluginLoader$2.execute(JavaPluginLoader.java:212)
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:59)
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:257)
        at net.minecraft.server.ServerConfigurationManager.disconnect(ServerConfigurationManager.java:115)
        at net.minecraft.server.NetServerHandler.disconnect(NetServerHandler.java:98)
        at org.bukkit.craftbukkit.entity.CraftPlayer.kickPlayer(CraftPlayer.java:124)
        at com.earth2me.essentials.PlayerWrapper.kickPlayer(PlayerWrapper.java:51)
        at com.earth2me.essentials.commands.Commandkick.run(Commandkick.java:38)
        at com.earth2me.essentials.commands.EssentialsCommand.run(EssentialsCommand.java:56)
        at com.earth2me.essentials.Essentials.onCommand(Essentials.java:567)
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:35)
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:85)
        at org.bukkit.craftbukkit.CraftServer.dispatchCommand(CraftServer.java:247)
        at net.minecraft.server.MinecraftServer.b(MinecraftServer.java:394)
        at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:379)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:285)
        at net.minecraft.server.ThreadServerApplication.run(SourceFile:394)

I get that everytime someone leaves.