DaemonUmbra

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

If you could provide a sampler report we might be able to help, otherwise some general tips would be: Uninstall Optifine if you have it installed We have had people claim they had no mods installed and their reports revealed Optifine, which isn't as universally beneficial as its community wants you to believe Make sure vsync is off Mojang's implementation of vsync is complete garbage, apparently

I seem to recall getting this error myself... I think it had something to do with caps, also I do what GitHub suggests and put those in a gradle.properties in my user folder so they're global and there's no risk of accidentally committing them

Does this impact the ability to play or are you just here to whine?

GatherDataEvent only fires during data runs, not during client or server runs

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

Who told you to use OnlyIn everywhere?

The launcher bundles 8 on Windows, which is one reason we can't use features of newer Java versions

It's not the responsibility of the Open Source Project (Forge) to maintain compatibility with the Closed Source Project (Optifine).

There is no way you could know you have the same problem from what the original user posted... response split to its own thread Your issue is using Java 15, and only certain versions of Forge are currently compatible.

You can This is accomplished by putting the mods in the server's mods folder. You must install Forge to .minecraft (the default location) unless you are doing something funny with your launcher. This is NOT how you make separate instances of Forge.

If you have Java installed correct you should be able to just double click the installer and Java will handle running it.

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.

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

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

You can't expect us to support every version ever released ad infinitum. That doesn't sound like a valid reason to not upgrade, and if that is indeed your reasoning you would probably look at getting a better PC if you plan on playing games.

maven-publish is preferred and I was able to get it working

Well that's a technic thing and is their fault for not being compatible with the official Minecraft Launcher, which Forge will always target.

User was banned for piracy. Buy the game.

https://paste.gg/p/anonymous/47eb336f970d400bb9f707d7aed7c776#pastefile1-l30 That's not a valid mod ID

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

Please provide the installer log. It will be named the same as the installer but with .log on the end: Installer: forge-<mc_version>-<forge_version>-installer.jar Log: forge-<mc_version>-<forge_version>-installer.jar.log Note: Windows hides file extensions by default, so unless you have set it to show file extensions it may show as below: Installer: forge-<mc_version>-<forge_version>-installer Log: forge-<mc_version>-<forge_version>-installer.jar

Don't touch the runconfigs yourself. Update the values in build.gradle and then run the task again to regen the runconfigs. If that doesn't fix it, post your debug.log, build.gradle, and mods.toml on one of the sites listed in the logs section of my signature below. (my antivirus and ISP both block the site you used before)

Such a thing would only work if the client is honest, and the client is capable of lying. This is the first step of an arms race that we've seen people on both sides ask about, we won't be giving recommendations.