You’re building your dream castle in Minecraft, everything’s perfect, and then—bam!—you get kicked from the server with a weird error: “Internal Exception: io.netty.handler.codec.DecoderException: Badly compressed packet – size of X is larger than protocol maximum of Y”. Or maybe something like “Received invalid custom payload”. Annoying, right?
This error is called the Custom Payload Error, and it pops up more often when you’re using mods, resource packs, or joining modded servers. But don’t worry! It’s fixable, and you don’t need to be a coding wizard to solve it.
TL;DR
The Custom Payload Error usually means there’s an issue with mods or plugins sending data between the server and your game. Update or remove conflicting mods, ensure server and client versions match, and use trusted sources for mods. It’s mostly about keeping things clean and compatible. And no, you’re not cursed—everyone gets this at some point!
What Is a Custom Payload Error?
First, let’s decode what this error means in simple terms.
In Minecraft, a “payload” is a fancy word for the information your game sends and receives while you play. For example, when a mod tells the server “Hey, I just added a new sword!”, that info gets sent as a payload.
A custom payload means this data is special — usually something added by a mod, not part of the original game.
If something goes wrong (like the data being too big or not formatted right), that’s when the dreaded custom payload error crashes the party.
When Does This Error Happen?
You’ll usually see it when:
- Joining a modded Minecraft server
- Playing with untested plugins or mods
- Using a version mismatch between your client and the server
- Downloading sketchy mods or resources
And sometimes… Minecraft just gets cranky for no reason.
Step-by-Step: How to Fix the Custom Payload Error
1. Restart Minecraft
Yeah, that sounds too simple. But sometimes it’s all you need. Close the game and launcher, wait a few seconds, then reopen it.
2. Check Your Mod List
If you’re using Forge or Fabric, check for mod conflicts.
Here’s how:
- Open the mods folder. Usually located at .minecraft/mods.
- Check that all mods match the Minecraft version you’re running.
- Remove mods you recently added — especially if the error started after adding them.
Still crashing? Try removing all mods and loading each one back in, one at a time. Boring, but effective.
3. Use the Same Version as the Server
If you’re playing on a multiplayer server, make sure your game version matches the server exactly.
Example:
- If the server runs Minecraft 1.20.1, your client should run the same.
- Same versions of Forge/Fabric are also important!
4. Use Reliable Mod Sources
Never download mods from random corners of the internet. Trust us, some sketchy mods are ticking time bombs.
Stick to sources like:
5. Disable or Update Plugins (For Server Hosts)
If you’re hosting the server, it might be you and not the players getting this error. A messed-up plugin on your server could be sending bad data.
Try this:
- Temporarily disable recently added plugins.
- Update all plugins — old ones often misbehave with newer Minecraft builds.
- Check server logs for clues!
6. Use Vanilla for Troubleshooting
Run Minecraft without any mods and try joining the server. If you’re able to get in normally, the issue is definitely mod or version-based.
7. Adjust Packet Size (Advanced)
Some modded servers allow you to tweak packet size settings. Be careful: Too much tinkering here can cause other stuff to break.
If you’re the server admin, check the following:
- Your server.properties file – though packet limits are not always exposed here
- Server-side mod configs (some allow custom limits)
- Replace or reconfigure any data-intensive mods
8. Update Forge, Fabric, or Your Launcher
A lot of crashes come from outdated launchers or frameworks.
Make sure you’re using the latest version of:
Extra Tips
Tip 1: Back up your saves before making changes. Always play it safe!
Tip 2: Ask others on the server if they’re crashing too. If they are, it’s probably a server-side issue.
Tip 3: Keep notes when changing mods — that way, if stuff breaks, you’ll know what changed.
Still Stuck?
If nothing works, take a screenshot of the error and get help.
Here’s where to turn:
Just be polite and provide info like:
- Your Minecraft version
- Forge/Fabric version
- Mod list or plugin list
- When the error started
Final Thoughts
Error messages might seem scary, but once you understand what’s going on, they’re basically Minecraft’s way of crying out for some TLC. Treat your mods with care, double-check versions, and don’t panic when things go boom.
The Custom Payload Error can be annoying, but with a little troubleshooting and some patience, you’ll be back to mining diamonds and fighting creepers faster than you can say “Download Complete!”
Now go patch up that server and build on, brave adventurer!