Plugin Help Anyone know what this error is? (VTeamCity)

[pool-3-thread-11/WARN]: org.apache.commons.lang.UnhandledException: Plugin Essentials vTeamCity generated an exception while executing task 104
at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:56)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoSuchMethodError: com.earth2me.essentials.ISettings.getSpawnOnJoinGroups()Ljava/util/List;
at com.earth2me.essentials.spawn.EssentialsSpawnPlayerListener.delayedJoin(EssentialsSpawnPlayerListener.java:75)
at com.earth2me.essentials.spawn.EssentialsSpawnPlayerListener$1.run(EssentialsSpawnPlayerListener.java:67)
at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftTask.run(CraftTask.java:53)
at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:53)
... 3 more


Unsure what this error is or what it's caused by. Can anyone give me some insight? thanks.

E.g is this essentials causing this? is this Factions? What would it be?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

What is vTeamCity though?

I don't have any plugins called vteamcity @timtower