Launcher problems

Fabric Loader: Could not find valid game provider!

What it looks like in the log

java.lang.RuntimeException: Could not find valid game provider!

How to fix it

  1. If using a game launcher (such as the official launcher, HMCL, or Prism), update the launcher to its latest build, launch the matching vanilla Minecraft version once to ensure its JAR is downloaded, and reinstall the Fabric profile.
  2. Delete the broken Fabric folder inside `.minecraft/versions/` and re-run the official Fabric Installer to regenerate a clean version JSON.
  3. If hosting a server with `fabric-server-launch.jar`, place the matching vanilla `server.jar` in the same directory and verify `fabric-server-launch.properties` points to it, or download the modern executable server JAR from the Fabric website.
  4. If developing a mod in IntelliJ IDEA, click 'Reload All Gradle Projects', run the `genIntellijRuns` Gradle task, and launch the client using the newly generated Gradle run configuration.
LoadersFabric, Server
SeverityStops the game
CategoryLauncher problems

Check your own log

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