Minecraft crash: Mod loading failed
The loader checked your mods before starting and found something it cannot run: a missing mod, a wrong version, a mod for another loader or the same mod twice.
Updated October 2, 2026. Fabric, NeoForge and Forge.
What you see
The game stops before the title screen. On Fabric:
Incompatible mods found!
net.fabricmc.loader.impl.FormattedException: Some of your mods are incompatible with the game or each other!
- Mod 'Example Mod' (examplemod) 2.1.0 requires version 0.110.0 or later of mod 'Fabric API' (fabric-api), but only the wrong version is present: 0.102.0!On NeoForge or Forge, an error screen and in the log:
Mod loading has failed
Missing or unsupported mandatory dependencies:
Mod ID: 'architectury', Requested by: 'examplemod', Expected range: '[13.0.0,)', Actual version: '[MISSING]'This is the kindest crash: the loader already says what is wrong. The fix is in the message.
Why it happens, and the fix for each
- A required mod is missing.
requires,[MISSING]: install that mod, in the version or range it names. - A required mod has the wrong version.
only the wrong version is present,Expected range: update or downgrade it to that range. - A mod needs another Minecraft or loader version. The required mod is
minecraft,fabricloader,neoforgeorforge: get the mod's version for your game, or update the loader. - Two mods cannot be together.
is incompatible with,breaks: the author said so. Keep one. - The same mod twice.
Duplicate mod,Found duplicate mods: delete the older file from themodsfolder. - A mod for another loader. A Fabric mod in a NeoForge game is skipped or rejected: get the version for your loader.
Let the game tell you
On NeoForge and Forge, the Modkeel Companion reads the failed load on the next start, names the mod in plain words and offers to turn it off or go back to the mods that last worked. (Fabric stops these before any mod runs, with the message above.) It backs up your worlds whenever your mods change. Free and open source, for Fabric, NeoForge and Forge.