It is the nightmare scenario for every server admin: you try to log in, and the server instantly crashes. You restart, try again, and it crashes again. The console screams java.lang.NullPointerException or Exception ticking world. You have encountered the dreaded "Ticking Entity" error.

Before you panic and delete your world save, stop. This error is specific, logical, and often completely fixable without losing your entire map. Whether you are running a vanilla server or a heavy modpack like "All the Mods" or "Better Minecraft," this guide will walk you through the technical "why" and the practical "how" of saving your world.

Understanding the Mechanics: What is a "Tick"?

To fix the problem, you must first understand how Minecraft functions. Minecraft is a loop. Ideally 20 times every second, the game server runs a "Tick." During a tick, the server updates every active element in loaded chunks: crops grow, water flows, mobs move, and machines process items.

A "Ticking Entity" error occurs when the code governing one specific object (an entity) encounters a critical failure during this update loop.

• Entities: Mobs, animals, players, dropped items, projectiles (arrows), and vehicles (minecarts/boats).
• Block Entities (Tile Entities): Blocks that hold data, such as Chests, Furnaces, Modded Machines, or Pipes.

When the server tries to process that specific entity's logic (e.g., a skeleton trying to pathfind, or a modded pipe trying to push an item), it encounters corrupted data—perhaps an invalid item ID, a null value where a number should be, or a conflict between two mods. The Java Virtual Machine (JVM) cannot resolve the error, throws an exception, and to prevent further corruption, it immediately shuts down the server.

Phase 1: Diagnosis - Reading the Crash Report

You cannot fix what you cannot find. The crash report is your roadmap. Do not just look at the console logs; you need the full crash report file generated in the /crash-reports/ folder.

Open the latest file (e.g., crash-2025-01-01_12.00.00-server.txt) and look for a section titled -- Entity being ticked -- or -- Block entity being ticked --. It will look something like this:

-- Entity being ticked --
Details:
    Entity Type: minecraft:zombie (net.minecraft.entity.monster.EntityZombie)
    Entity ID: 4522
    Name: Zombie
    Exact location: -234.50, 67.00, 1056.30
    Block location: World: (-235,67,1056), Chunk: (at 5,4,0 in -15,66; contains blocks -240,0,1056 to -225,255,1071)
    Region: (-1,2; contains chunks -32,64 to -1,95, blocks -512,0,1024 to -1,255,1535)

Key Data Points to Save:

• Entity Type: What caused it? (e.g., minecraft:zombie or mekanism:robit)
• Exact Location: The X, Y, Z coordinates (e.g., -234, 67, 1056).
• Region/Chunk: Essential for more advanced deletion methods later.

Phase 2: The "Silver Bullet" (Forge Configs)

If you are running a modded server (Forge or NeoForge), the developers have provided a built-in fail-safe mechanism that is often disabled by default. This is the safest and easiest fix because it asks the server to simply delete the bad entity instead of crashing.

Note for King's Domain Clients: Our "Auto-Fix" tool in the panel attempts this automatically, but doing it manually ensures precision.

For Minecraft 1.13 and Newer (1.16, 1.18, 1.20+)

In modern Minecraft versions, this configuration is located in the serverconfig folder inside your specific world save, not the main config folder.

1. Stop your server completely.
2. Navigate to your world folder: /world/serverconfig/.
3. Open forge-server.toml.
4. Find the section [general].
5. Change the following two lines from false to true:

   removeErroringEntities = true
   removeErroringBlockEntities = true

6. Save the file and start the server.

For Minecraft 1.12.2 and Older

For the golden age of modding, the config is located in the main server configuration folder.

1. Stop the server.
2. Navigate to the root /config/ folder.
3. Open forge.cfg.
4. Find these lines and set them to true:

   B:removeErroringEntities=true
   B:removeErroringTileEntities=true

5. Restart the server.

Crucial Step: Once the server boots successfully and the bad entity is deleted (check the console for "Removed erroring entity" messages), stop the server and revert these settings to false. Leaving them on permanently can hide severe mod bugs and cause items to vanish unexpectedly.

Phase 3: Command Line Surgery

If you are on Vanilla Minecraft, or if the Forge config didn't work (perhaps the crash happens before the config loads), you can try using commands. This usually requires the server to stay online for at least a few seconds, or for you to prevent the chunk from loading immediately.

Method A: The /kill Command (Vanilla)

If the server crashes only when a player logs in, it means the bad entity is in the chunks that player is loading.

1. Start the server but do not join.
2. In the server console, run this command to kill all entities of the type identified in your crash report (e.g., zombies):

   /kill @e[type=minecraft:zombie]

3. If you don't care about collateral damage and just want the server to work, you can kill everything (warning: this kills villagers, pets, and item frames):

   /kill @e[type=!player]

Method B: The /cofh killall Command (Modded)

If you have the CoFH Core mod installed (common in many modpacks), it offers a more powerful command that works on unloaded chunks better than vanilla commands.

/cofh killall [entity_name]

Method C: Peaceful Mode

If the crash report indicates a hostile mob (Zombie, Skeleton, Creeper, etc.) is the culprit:

1. Open server.properties.
2. Change difficulty=normal to difficulty=peaceful.
3. Start the server. The game effectively deletes all hostile mobs upon loading.
4. Once loaded, stop the server and switch back to your preferred difficulty.

Phase 4: The Surgical Approach (NBTExplorer)

If Forge configs fail and the server won't stay up long enough for commands, you must perform surgery on the world file itself. For this, we use a tool called NBTExplorer. This allows you to modify the game's internal data (NBT) while the server is offline.

Step-by-Step Guide to Deleting an Entity with NBTExplorer:

1. Backup: Download your /world/ folder to your PC. Do not edit files directly on the server via FTP.
2. Install NBTExplorer: Download and install this open-source tool.
3. Locate the Region File: Look at your crash report again. Under "Entity being ticked," look for the Region: line (e.g., Region: (-1, 2)). Navigate to /world/region/ and find the file named r.-1.2.mca.
4. Open the Region File: Open this .mca file in NBTExplorer.
5. Find the Chunk: The crash report also gave you Chunk coordinates (e.g., Chunk: (at 5, 4, 0...)). In NBTExplorer, locate the chunk named Chunk [5, 4].
6. Find the Entity: Expand the chunk tree: Level -> Entities (for mobs) or TileEntities (for blocks). Browse the list of children. Look for the entry where the id matches your crash report (e.g., minecraft:zombie) and the Pos (Position) matches the coordinates.
7. Delete: Right-click the specific compound tag for that entity and select Delete.
8. Save: Click the Save icon. Upload the modified .mca file back to your server, replacing the old one.

Phase 5: The Nuclear Option (Chunk Deletion)

If you cannot isolate the specific entity, or if the chunk itself is corrupted (Ticking World Error), you may need to delete the entire chunk. This will reset that 16x16 area to its original state, as if you had just generated the world. Any buildings in that chunk will be lost.

While you can delete chunks via NBTExplorer, a more visual tool like MCASelector is recommended for this.

1. Download your world to your PC.
2. Open the world in MCASelector.
3. Use the coordinates from the crash report to find the specific area.
4. Select the chunk (or surrounding chunks) and choose Selection -> Delete Selected Chunks.
5. Upload the world back to the server. Minecraft will regenerate those chunks fresh when you log in.

Prevention: Stability Starts with Hosting

Ticking entities often arise from server lag causing synchronization issues during the save process, or from running out of RAM during heavy operations.

At King's Domain, our high-performance hardware significantly reduces the "tick lag" that can lead to data corruption. Furthermore, our automated off-site backups mean that if a world does become irretrievably corrupted, you are never more than a few clicks away from a working restore point.

Conclusion

The "Ticking Entity" error is intimidating, but it is purely data. It is a specific number in a specific file that the game doesn't like. By following these steps—starting with the easy Forge configs and moving to the surgical NBT editing—you can almost always recover your world.

Stop panic-deleting your worlds. Fix them. And if you want a host that supports you through the technical grit, check out our plans below.