First, my problem was that the launcher set a wrong /.minecraft/ directory as default and as expected there were none of the files that the process was expecting to find, so I selected the correct one and the problem didn't show any more.
Then this error showed up and I don't know how to fix it. I read some forums about this, but I already checked if my mods folder was duplicated or if there was any mod that the process wasn't expecting, but the folder is empty as I don't use any.
I use Optifine intended as a modified version of the game and not a mod.
See the error log below for more information:
[TECKNIX-LAUNCHER] [2022-10-0 10:14] [INFO] Load completed.
[TECKNIX-LAUNCHER] [2022-10-0 10:16] [INFO] Starting launch sequence.
[TECKNIX-LAUNCHER] [2022-10-0 10:16] [INFO] Java runtime is already downloaded, continuing with launch.
[TECKNIX-LAUNCHER] [2022-10-0 10:16] [INFO] Downloading and verifying dependencies.
[TECKNIX-LAUNCHER] [2022-10-0 10:16] [INFO] Found matching version for: FORGE-1.8.9!
[TECKNIX-LAUNCHER] [2022-10-0 10:16] [INFO] Downloading java runtime.
[TECKNIX-LAUNCHER] [2022-10-0 10:16] [INFO] Executable path: /home/pika/.tecknixsoftware/tecknixclient/runtimes/jre-8u51/bin/java!
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] Downloading and verifying natives.
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] Everything is valid and game is ready to launch!
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] Building arguments.
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] Arguments have been set, ready to launch game.
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] Due to the operating system we ran chmod on the java executable.
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:06] [main/INFO]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: Using primary tweak class name net.minecraftforge.fml.common.launcher.FMLTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: Loading tweak class name optifine.OptiFineForgeTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: Loading tweak class name com.tecknix.v1_8.injection.tweaker.TecknixTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: Forge Mod Loader version 11.15.1.2318 for Minecraft 1.8.9 loading
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: Java is Java HotSpot(TM) 64-Bit Server VM, version 1.8.0_51, running on Linux:amd64:5.15.0-52-generic, installed at /home/pika/.tecknixsoftware/tecknixclient/runtimes/jre-8u51
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: Calling tweak class optifine.OptiFineForgeTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: [optifine.OptiFineForgeTweaker:dbg:56]: OptiFineForgeTweaker: acceptOptions
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: [optifine.OptiFineForgeTweaker:dbg:56]: OptiFineForgeTweaker: injectIntoClassLoader
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: [optifine.OptiFineClassTransformer:dbg:242]: OptiFine ClassTransformer
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: [optifine.OptiFineClassTransformer:dbg:242]: OptiFine ZIP file: /home/pika/.tecknixsoftware/tecknixclient/versions/FORGE-1.8.9/dependencies/OptiFine_1.8.9_HD_U_M5.jar
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:07] [main/INFO]: Calling tweak class com.tecknix.v1_8.injection.tweaker.TecknixTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:08] [main/INFO]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:08] [main/INFO]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLDeobfTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:08] [main/INFO]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:08] [main/INFO]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[10:17:08] [main/INFO]: Calling tweak class net.minecraftforge.fml.relauncher.CoreModManager$FMLPluginWrapper
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:11] [main/INFO]: Found valid fingerprint for Minecraft Forge. Certificate fingerprint e3c3d50c7c986df74c645c0ac54639741c90a557
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:13] [main/INFO]: Found valid fingerprint for Minecraft. Certificate fingerprint cd99959656f753dc28d863b46769f7f8fbaefcfc
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:13] [main/INFO]: Calling tweak class net.minecraftforge.fml.relauncher.CoreModManager$FMLPluginWrapper
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:13] [main/INFO]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLDeobfTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:14] [main/INFO]: Loading tweak class name net.minecraftforge.fml.common.launcher.TerminalTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:14] [main/INFO]: Calling tweak class net.minecraftforge.fml.common.launcher.TerminalTweaker
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:14] [main/INFO]: [optifine.OptiFineForgeTweaker:dbg:56]: OptiFineForgeTweaker: getLaunchArguments
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:14] [main/INFO]: Launching wrapped minecraft {net.minecraft.client.main.Main}
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:19] [main/INFO]: [net.minecraft.client.main.Main:main:57]: Completely ignored arguments: [mojang, ]
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:20] [Client thread/INFO]: Setting user: TecknixLaunch
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:20] [Client thread/ERROR]: Unable to launch
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_51]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_51]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_51]
at java.lang.reflect.Method.invoke(Method.java:497) ~[?:1.8.0_51]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:159) [launchwrapper-of-2.2.jar:2.2]
at net.minecraft.launchwrapper.Launch.main(Launch.java:30) [launchwrapper-of-2.2.jar:2.2]
Caused by: java.lang.NoClassDefFoundError: net/minecraftforge/fml/common/registry/RegistryDelegate
at net.minecraftforge.fml.common.registry.PersistentRegistryManager$PersistentRegistry.createRegistry(PersistentRegistryManager.java:85) ~[PersistentRegistryManager$PersistentRegistry.class:?]
at net.minecraftforge.fml.common.registry.PersistentRegistryManager$PersistentRegistry.access$000(PersistentRegistryManager.java:46) ~[PersistentRegistryManager$PersistentRegistry.class:?]
at net.minecraftforge.fml.common.registry.PersistentRegistryManager.createRegistry(PersistentRegistryManager.java:135) ~[PersistentRegistryManager.class:?]
at net.minecraftforge.fml.common.registry.GameData.<init>(GameData.java:114) ~[GameData.class:?]
at net.minecraftforge.fml.common.registry.GameData.<clinit>(GameData.java:40) ~[GameData.class:?]
at net.minecraft.block.Block.<clinit>(Block.java:41) ~[afh.class:?]
at net.minecraft.init.Bootstrap.func_151354_b(Bootstrap.java:512) ~[kb.class:?]
at net.minecraft.client.Minecraft.<init>(Minecraft.java:320) ~[ave.class:?]
at net.minecraft.client.main.Main.main(SourceFile:124) ~[Main.class:?]
... 6 more
Caused by: java.lang.ClassNotFoundException: net.minecraftforge.fml.common.registry.RegistryDelegate
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:186) ~[launchwrapper-of-2.2.jar:2.2]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_51]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_51]
at net.minecraftforge.fml.common.registry.PersistentRegistryManager$PersistentRegistry.createRegistry(PersistentRegistryManager.java:85) ~[PersistentRegistryManager$PersistentRegistry.class:?]
at net.minecraftforge.fml.common.registry.PersistentRegistryManager$PersistentRegistry.access$000(PersistentRegistryManager.java:46) ~[PersistentRegistryManager$PersistentRegistry.class:?]
at net.minecraftforge.fml.common.registry.PersistentRegistryManager.createRegistry(PersistentRegistryManager.java:135) ~[PersistentRegistryManager.class:?]
at net.minecraftforge.fml.common.registry.GameData.<init>(GameData.java:114) ~[GameData.class:?]
at net.minecraftforge.fml.common.registry.GameData.<clinit>(GameData.java:40) ~[GameData.class:?]
at net.minecraft.block.Block.<clinit>(Block.java:41) ~[afh.class:?]
at net.minecraft.init.Bootstrap.func_151354_b(Bootstrap.java:512) ~[kb.class:?]
at net.minecraft.client.Minecraft.<init>(Minecraft.java:320) ~[ave.class:?]
at net.minecraft.client.main.Main.main(SourceFile:124) ~[Main.class:?]
... 6 more
Caused by: java.lang.SecurityException: class "net.minecraftforge.fml.common.registry.RegistryDelegate"'s signer information does not match signer information of other classes in the same package
at java.lang.ClassLoader.checkCerts(ClassLoader.java:895) ~[?:1.8.0_51]
at java.lang.ClassLoader.preDefineClass(ClassLoader.java:665) ~[?:1.8.0_51]
at java.lang.ClassLoader.defineClass(ClassLoader.java:758) ~[?:1.8.0_51]
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) ~[?:1.8.0_51]
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:177) ~[launchwrapper-of-2.2.jar:2.2]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_51]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_51]
at net.minecraftforge.fml.common.registry.PersistentRegistryManager$PersistentRegistry.createRegistry(PersistentRegistryManager.java:85) ~[PersistentRegistryManager$PersistentRegistry.class:?]
at net.minecraftforge.fml.common.registry.PersistentRegistryManager$PersistentRegistry.access$000(PersistentRegistryManager.java:46) ~[PersistentRegistryManager$PersistentRegistry.class:?]
at net.minecraftforge.fml.common.registry.PersistentRegistryManager.createRegistry(PersistentRegistryManager.java:135) ~[PersistentRegistryManager.class:?]
at net.minecraftforge.fml.common.registry.GameData.<init>(GameData.java:114) ~[GameData.class:?]
at net.minecraftforge.fml.common.registry.GameData.<clinit>(GameData.java:40) ~[GameData.class:?]
at net.minecraft.block.Block.<clinit>(Block.java:41) ~[afh.class:?]
at net.minecraft.init.Bootstrap.func_151354_b(Bootstrap.java:512) ~[kb.class:?]
at net.minecraft.client.Minecraft.<init>(Minecraft.java:320) ~[ave.class:?]
at net.minecraft.client.main.Main.main(SourceFile:124) ~[Main.class:?]
... 6 more
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] Exception in thread "Client thread"
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:20] [Client thread/INFO]: [java.lang.ThreadGroup:uncaughtException:1052]: net.minecraftforge.fml.relauncher.FMLSecurityManager$ExitTrappedException
[10:17:20] [Client thread/INFO]: [java.lang.ThreadGroup:uncaughtException:1052]: at net.minecraftforge.fml.relauncher.FMLSecurityManager.checkPermission(FMLSecurityManager.java:30)
[10:17:20] [Client thread/INFO]: [java.lang.ThreadGroup:uncaughtException:1052]: at java.lang.SecurityManager.checkExit(SecurityManager.java:761)
[10:17:20] [Client thread/INFO]: [java.lang.ThreadGroup:uncaughtException:1052]: at java.lang.Runtime.exit(Runtime.java:107)
[10:17:20] [Client thread/INFO]: [java.lang.ThreadGroup:uncaughtException:1052]: at java.lang.System.exit(System.java:971)
[10:17:20] [Client thread/INFO]: [java.lang.ThreadGroup:uncaughtException:1052]: at net.minecraft.launchwrapper.Launch.launch(Launch.java:162)
[TECKNIX-LAUNCHER] [2022-10-0 10:17] [INFO] [10:17:20] [Client thread/INFO]: [java.lang.ThreadGroup:uncaughtException:1052]: at net.minecraft.launchwrapper.Launch.main(Launch.java:30)
