Hello,
I am using the Crundeecraft modpack, but I had it before this whole problem emerged, so it's probably not the modpack itself. I do have to note that since some time Not Enough Items got disabled, however I can still join my server.
My server keeps crashing because of an "ticking entity" this happens at random moments and it is not an issue when starting or when a player joins. It keeps happening more and more (prior it was each hour, now it's each five minutes, which is really irritating considering the fact it takes 10 - 40 minutes to start the server.)
Here is the log about the crash:
| [17:14:18] [Server thread/ERROR]: Encountered an unexpected exception | |
| 58 | net.minecraft.util.ReportedException: Ticking entity |
| 59 | at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:642) ~[MinecraftServer.class:?] |
| 60 | at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:334) ~[lt.class:?] |
| 61 | at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547) ~[MinecraftServer.class:?] |
| 62 | at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:396) [MinecraftServer.class:?] |
| 63 | at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685) [li.class:?] |
| 64 | Caused by: java.lang.NullPointerException |
| 65 | at net.minecraft.entity.ai.EntityLookHelper.func_75651_a(SourceFile:18) ~[tu.class:?] |
| 66 | at net.minecraft.entity.ai.EntityAIAttackOnCollide.func_75246_d(EntityAIAttackOnCollide.java:93) ~[uq.class:?] |
| 67 | at net.minecraft.entity.ai.EntityAITasks.func_75774_a(SourceFile:103) ~[uj.class:?] |
| 68 | at net.minecraft.entity.EntityLiving.func_70619_bc(EntityLiving.java:540) ~[sw.class:?] |
| 69 | at net.minecraft.entity.EntityLivingBase.func_70636_d(EntityLivingBase.java:1774) ~[sv.class:?] |
| 70 | at net.minecraft.entity.EntityLiving.func_70636_d(EntityLiving.java:367) ~[sw.class:?] |
| 71 | at net.minecraft.entity.monster.EntityMob.func_70636_d(SourceFile:25) ~[yg.class:?] |
| 72 | at net.minecraft.entity.monster.EntityZombie.func_70636_d(EntityZombie.java:217) ~[yq.class:?] |
| 73 | at net.minecraft.entity.EntityLivingBase.func_70071_h_(EntityLivingBase.java:1611) ~[sv.class:?] |
| 74 | at net.minecraft.entity.EntityLiving.func_70071_h_(EntityLiving.java:206) ~[sw.class:?] |
| 75 | at net.minecraft.entity.monster.EntityMob.func_70071_h_(SourceFile:30) ~[yg.class:?] |
| 76 | at net.minecraft.entity.monster.EntityZombie.func_70071_h_(EntityZombie.java:303) ~[yq.class:?] |
| 77 | at net.minecraft.world.World.func_72866_a(World.java:2070) ~[ahb.class:?] |
| 78 | at net.minecraft.world.WorldServer.func_72866_a(WorldServer.java:648) ~[mt.class:?] |
| 79 | at net.minecraft.world.World.func_72870_g(World.java:2034) ~[ahb.class:?] |
| 80 | at net.minecraft.world.World.func_72939_s(World.java:1887) ~[ahb.class:?] |
| 81 | at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:489) ~[mt.class:?] |
| 82 | at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:636) ~[MinecraftServer.class:?] |
| 83 | ... 4 more |
| 84 | [17:14:18] [Server thread/ERROR]: This crash report has been saved to: /aternos/server/./crash-reports/crash-2019-04-17_17.14.18-server.txt |
Here is the full log of the latest crash:
I would think this would stop if I created a new world, but that would erase all my nice survival buildings 
If anyone could help me out that would be awesome!