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Packet Fixer Mod Wiki & Guide

Java EditionModGuides 4FAQ 20Related mods 48

Packet Fixer Mod fixes many common errors related to game data packets and NBTs. This mod is very helpful for players who use large modpacks, as it improves compatibility between different mods.

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Contents (4)
  1. Guides
  2. Frequently asked questions
  3. Gallery
  4. You May Also Like

Guides

Step-by-step, in-game.

How to Diagnose Which Packet or NBT Error Is Crashing Your GameRead the Log First Before changing anything, find the actual error. Open your latest log file and search for terms…How to Fix Connection Timeouts and Kicks on a Modded ServerThe Symptom You join a modded server and get kicked shortly after connecting, or you time out while loading into a…How to Keep Packet Fixer Working Correctly in a Large ModpackInstall It in the Right Places Packet Fixer only helps when every side of the connection has it. In singleplayer that…How to Stop Large Modpack Crashes Caused by Oversized NBT and PacketsWhy the Crash Happens In a large modpack, machines, backpacks , and storage systems can hold enormous amounts of…

Frequently asked questions

What does Packet Fixer actually do?
It raises the size limits on the game's data packets and NBT tags so oversized data no longer crashes the game. This mostly matters on large modpacks where mods send bigger payloads than vanilla expects.
Do I need to configure anything after installing it?
Usually no — the mod works out of the box with sensible defaults. You only need to touch the config if you still hit size-related crashes or want to tune memory behavior.
Where do I find the Packet Fixer config?
It's a standard Forge/NeoForge config file, so you can edit it from the mod list's config button in-game or from the config folder. Changes typically need a game restart to take effect.
Will Packet Fixer fix my 'NBT too big' crash?
Yes, that's one of its main jobs — it increases the allowed NBT tag size so oversized tags no longer throw an exception. If the crash persists, the tag may be corrupt rather than just large, so check the mod producing it.

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