DaemonUmbra

Delete C:\Users\steph\AppData\Roaming\.minecraft\config\fml.toml and try again

Try deleting C:\Users\dog\AppData\Roaming\.minecraft\config\biomesoplenty\biomes.json and try again

1.7 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

No, that looks like an older debug.log that has been compressed into an archive. Do note that Windows by default hides known file extensions, I recommend going to View and checking the box that says "File name extensions"

That's a vanilla bug that's made more common in Forge, there should be a quick fix implemented in Forge for 1.16.3

Please keep this forum in English. Please make your own thread.

Don't make custom clients. MCP is dead. We don't support 1.8.

I've just noticed where you're looking, that's not where it generates. It generates in run/logs

Open Intellij's Gradle settings (the wrench in the Gradle Panel) and for both "Build and run using" and "Run tests using", select idea instead of Gradle, then try running again

Did you use one of the sites listed in my signature below?

Please provide debug.log (more info on where it is and how to provide it in my signature below, just expand the spoiler)

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.

1.12 is no longer supported on this forum. Please update to a modern version of Minecraft to receive support.