BONELAB is one of the most heavily modded Unity games, and MelonLoader is the backbone of its code modding ecosystem. However, BONELAB uses the Il2Cpp backend, receives frequent major updates, and depends on complex framework mods such as BoneLib. Because of this combination, crashes are extremely common if anything is even slightly out of sync.
Most Melonloader Crashing BONELAB fall into three clear categories. Each category has distinct symptoms and reliable fixes.
Category A: MelonLoader Initialization Crash
This is the most severe type of crash. The game closes almost immediately after launch. In many cases, the MelonLoader console never appears or disappears instantly. This means MelonLoader failed to inject into BONELAB at startup.
BONELAB Patch and MelonLoader Version Mismatch
BONELAB releases large patches regularly. Each major patch can change internal Unity and Il2Cpp structures. When this happens, older MelonLoader versions may no longer be compatible.
Symptoms
- Instant crash on launch
- No clear error message
- MelonLoader console closes immediately
Fix
- Update MelonLoader using the official installer
- Check the BONELAB modding community to confirm the minimum required MelonLoader version for your current game patch
- Reinstall MelonLoader if necessary instead of overwriting files
Missing Runtime Dependencies for Il2Cpp
BONELAB uses Il2Cpp, which has strict runtime requirements.
Common causes
- Missing .NET 6 Desktop Runtime
- Missing Microsoft Visual C++ Redistributable
Fix
- Install the .NET 6 Desktop Runtime or newer, matching x64 architecture
- Install Microsoft Visual C++ 2015 to 2019 Redistributable x64
- Restart your system after installing runtimes
Category B: Mod or Plugin Conflict Crash
In this case, MelonLoader starts normally. The console appears and begins listing mods, but the game crashes during loading, often before the main menu or when entering a level.
Outdated Mods After a BONELAB Update
After a BONELAB patch, many mods break because they reference game methods that no longer exist.
Symptoms
- Crash occurs after a specific mod name appears in the console
- Log shows missing method or null reference errors
Fix
- Remove all files from the Mods and Plugins folders
- Launch the game with only MelonLoader installed
- Add mods back one at a time
- Always update core frameworks like BoneLib first
Missing or Incorrect Framework Dependencies
Most BONELAB mods depend on shared frameworks such as BoneLib or Fusion. If these are missing, outdated, or placed incorrectly, dependent mods will crash during initialization.
Symptoms
- Errors referencing BoneLib or other framework assemblies
- Mods fail immediately during loading
Fix
- Download the correct version of the required framework
- Place framework DLL files in the Plugins folder
- Ensure the framework version matches your BONELAB patch
Category C: Installation and File Integrity Issues
These crashes are caused by corrupted files, incomplete installs, or security software interference.
Corrupted MelonLoader Installation
Using third-party mod managers or interrupted installs can leave MelonLoader in a broken state.
Symptoms
- Errors indicating missing bootstrap or loader files
- Inconsistent crashing behavior
Fix
- Perform a clean reinstall
- Delete the MelonLoader, Mods, Plugins, and UserData folders
- Remove version.dll and dobby.dll from the BONELAB root directory
- Reinstall MelonLoader using the official installer
Antivirus or Permission Blocking
Because MelonLoader injects code into the game process, antivirus software may silently block or delete its files.
Symptoms
- Game fails to launch with no visible error
- MelonLoader files disappear after installation
Fix
- Check antivirus or Windows Defender quarantine history
- Restore any MelonLoader related files
- Add the BONELAB game folder to antivirus exclusions
- Run the installer and game as administrator
How to Identify the Exact Crash Cause Using Logs
Logs are the most reliable way to diagnose BONELAB crashes.
Locate the Log Files
Navigate to
BONELAB\MelonLoader\Logs
Open the Latest Log
Open the most recent file named similar to
MelonLoader_YYYY-MM-DD_HH-MM-SS.log
Read the Final Lines
Scroll to the bottom of the log. The final error usually includes:
- The exception type
- The name of the mod or plugin that caused the crash
Common errors include missing methods or null references tied directly to outdated mods or frameworks.
Final Notes
Most MelonLoader crashes in BONELAB are caused by version mismatches. Keeping MelonLoader, BONELAB, and core frameworks like BoneLib fully updated solves the majority of issues. Always verify compatibility after major game patches and rely on log files to pinpoint the exact problem.
For stability, always download MelonLoader from the official source:
https://melonloader.pro/download-melonloader/
MelonLoader official website
https://melonloader.pro/
MelonLoader GitHub
https://github.com/LavaGang/MelonLoader