Issue Description:

An error occurred in the background of the server. The trigger reason is unknown.

What happens:

Console outputs duplicate error content.
I don't know if I should report it to you
Sorry, my English is not good. I'm Chinese

Affected Versions (Do not use "latest"):

• EnderIO:5.1.55
• EnderCore:0.5.73
• Minecraft:1.12.2
• Forge:2847
• SpongeForge? no
• Optifine? no
• Server.

Your most recent log file where the issue was present:

[19:38:34] [Server thread/WARN] [Minecraft]: Unknown target reason, please report on the issue tracker java.lang.Exception: null at net.minecraft.entity.EntityLiving.setGoalTarget(EntityLiving.java:193) [vq.class:?] at net.minecraft.entity.monster.EntityEnderman.setGoalTarget(EntityEnderman.java:107) [acu.class:?] at net.minecraft.entity.monster.EntityEnderman.func_70624_b(EntityEnderman.java:102) [acu.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.handlers.EndermanAttractionHandler.tick(EndermanAttractionHandler.java:23) [EndermanAttractionHandler.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.TileAttractor.tickTrackedEntities(TileAttractor.java:83) [TileAttractor.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.TileAttractor.processTasks(TileAttractor.java:126) [TileAttractor.class:?] at crazypants.enderio.base.machine.base.te.AbstractMachineEntity.doUpdate(AbstractMachineEntity.java:220) [AbstractMachineEntity.class:?] at crazypants.enderio.base.machine.baselegacy.AbstractPoweredMachineEntity.doUpdate(AbstractPoweredMachineEntity.java:62) [AbstractPoweredMachineEntity.class:?] at com.enderio.core.common.TileEntityBase.func_73660_a(TileEntityBase.java:49) [TileEntityBase.class:?] at net.minecraft.world.World.func_72939_s(World.java:2132) [amu.class:?] at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:756) [oo.class:?] at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:908) [MinecraftServer.class:?] at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:472) [nz.class:?] at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:778) [MinecraftServer.class:?] at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:632) [MinecraftServer.class:?] at java.lang.Thread.run(Unknown Source) [?:1.8.0_211] [19:38:34] [Server thread/WARN] [Minecraft]: Unknown target reason, please report on the issue tracker java.lang.Exception: null at net.minecraft.entity.EntityLiving.setGoalTarget(EntityLiving.java:193) [vq.class:?] at net.minecraft.entity.monster.EntityEnderman.setGoalTarget(EntityEnderman.java:107) [acu.class:?] at net.minecraft.entity.monster.EntityEnderman.func_70624_b(EntityEnderman.java:102) [acu.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.handlers.EndermanAttractionHandler.tick(EndermanAttractionHandler.java:23) [EndermanAttractionHandler.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.TileAttractor.tickTrackedEntities(TileAttractor.java:83) [TileAttractor.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.TileAttractor.processTasks(TileAttractor.java:126) [TileAttractor.class:?] at crazypants.enderio.base.machine.base.te.AbstractMachineEntity.doUpdate(AbstractMachineEntity.java:220) [AbstractMachineEntity.class:?] at crazypants.enderio.base.machine.baselegacy.AbstractPoweredMachineEntity.doUpdate(AbstractPoweredMachineEntity.java:62) [AbstractPoweredMachineEntity.class:?] at com.enderio.core.common.TileEntityBase.func_73660_a(TileEntityBase.java:49) [TileEntityBase.class:?] at net.minecraft.world.World.func_72939_s(World.java:2132) [amu.class:?] at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:756) [oo.class:?] at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:908) [MinecraftServer.class:?] at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:472) [nz.class:?] at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:778) [MinecraftServer.class:?] at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:632) [MinecraftServer.class:?] at java.lang.Thread.run(Unknown Source) [?:1.8.0_211] [19:38:38] [Server thread/WARN] [Minecraft]: Unknown target reason, please report on the issue tracker java.lang.Exception: null at net.minecraft.entity.EntityLiving.setGoalTarget(EntityLiving.java:193) [vq.class:?] at net.minecraft.entity.monster.EntityEnderman.setGoalTarget(EntityEnderman.java:107) [acu.class:?] at net.minecraft.entity.monster.EntityEnderman.func_70624_b(EntityEnderman.java:102) [acu.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.handlers.EndermanAttractionHandler.tick(EndermanAttractionHandler.java:23) [EndermanAttractionHandler.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.TileAttractor.tickTrackedEntities(TileAttractor.java:83) [TileAttractor.class:?] at crazypants.enderio.machines.machine.obelisk.attractor.TileAttractor.processTasks(TileAttractor.java:126) [TileAttractor.class:?] at crazypants.enderio.base.machine.base.te.AbstractMachineEntity.doUpdate(AbstractMachineEntity.java:220) [AbstractMachineEntity.class:?] at crazypants.enderio.base.machine.baselegacy.AbstractPoweredMachineEntity.doUpdate(AbstractPoweredMachineEntity.java:62) [AbstractPoweredMachineEntity.class:?] at com.enderio.core.common.TileEntityBase.func_73660_a(TileEntityBase.java:49) [TileEntityBase.class:?] at net.minecraft.world.World.func_72939_s(World.java:2132) [amu.class:?] at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:756) [oo.class:?] at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:908) [MinecraftServer.class:?] at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:472) [nz.class:?] at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:778) [MinecraftServer.class:?] at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:632) [MinecraftServer.class:?] at java.lang.Thread.run(Unknown Source) [?:1.8.0_211]

That code that is telling you to report the issue on "the" issue tracker was added by another mod. Sadly they forgot to add the information what issue tracker it should be reported, but it certainly isn't ours.

Sorry, feel free to yell at them once you found out who "they" are...

Thanks. Is there any other way to find the Mod that actually caused the error?

You could check the startup log if any mod says that they are adding "setGoalTarget". Other than that, it's just the usual "remove coremods until it doesn't happen anymore"...

At least the number of coremods isn't that high usually. (Note: only coremods can add new methods to vanilla objects)