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Currently supported: All versions

Forge crash, java.lang.NoClassDefFoundError

YoshiGPLS
in Support & Bug Reports

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Spoiler

---- Minecraft Crash Report ----

WARNING: coremods are present:
  Skytils On Top (Skytils-1.1.2.jar)
  SkyblockAddonsLoadingPlugin (SkyblockAddons-1.5.5-for-MC-1.8.9.jar)
  FMLLoadingPlugin (Scrollable Tooltips-1.4 (1.8.9).jar)
Contact their authors BEFORE contacting forge

// Don't do that.

Time: 3/9/22 3:47 PM
Description: Initializing game

java.lang.NoClassDefFoundError: net/minecraft/client/gui/Gui
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at gg.essential.loader.stage2.relaunch.RelaunchClassLoader.findClassImpl(RelaunchClassLoader.java:71)
    at gg.essential.loader.stage2.relaunch.IsolatedClassLoader.loadClass(IsolatedClassLoader.java:78)
    at org.apache.logging.log4j.core.impl.ThrowableProxy.loadClass(ThrowableProxy.java:459)
    at org.apache.logging.log4j.core.impl.ThrowableProxy.resolvePackageData(ThrowableProxy.java:395)
    at org.apache.logging.log4j.core.impl.ThrowableProxy.<init>(ThrowableProxy.java:97)
    at org.apache.logging.log4j.core.impl.Log4jLogEvent.<init>(Log4jLogEvent.java:114)
    at org.apache.logging.log4j.core.impl.Log4jLogEvent.<init>(Log4jLogEvent.java:90)
    at org.apache.logging.log4j.core.impl.DefaultLogEventFactory.createEvent(DefaultLogEventFactory.java:49)
    at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:365)
    at org.apache.logging.log4j.core.Logger.log(Logger.java:110)
    at org.apache.logging.log4j.spi.AbstractLogger.log(AbstractLogger.java:1448)
    at net.minecraftforge.fml.relauncher.FMLRelaunchLog.log(FMLRelaunchLog.java:83)
    at net.minecraftforge.fml.common.FMLLog.log(FMLLog.java:40)
    at net.minecraftforge.fml.common.LoadController.transition(LoadController.java:138)
    at net.minecraftforge.fml.common.Loader.preinitializeMods(Loader.java:559)
    at net.minecraftforge.fml.client.FMLClientHandler.beginMinecraftLoading(FMLClientHandler.java:243)
    at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:417)
    at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:329)
    at net.minecraft.client.main.Main.main(SourceFile:124)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at gg.essential.loader.stage2.relaunch.Relaunch.relaunch(Relaunch.java:124)
    at gg.essential.loader.stage2.EssentialLoader.addToClasspath(EssentialLoader.java:92)
    at gg.essential.loader.stage2.EssentialLoaderBase.addToClasspath(EssentialLoaderBase.java:328)
    at gg.essential.loader.stage2.EssentialLoaderBase.load(EssentialLoaderBase.java:143)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at gg.essential.loader.stage1.EssentialLoaderBase.load(EssentialLoaderBase.java:110)
    at gg.essential.loader.stage1.EssentialSetupTweaker.<init>(EssentialSetupTweaker.java:44)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
    at gg.essential.loader.stage0.EssentialSetupTweaker.loadStage1(EssentialSetupTweaker.java:111)
    at gg.essential.loader.stage0.EssentialSetupTweaker.<init>(EssentialSetupTweaker.java:34)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
    at java.lang.Class.newInstance(Class.java:442)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:98)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
Caused by: java.lang.ClassNotFoundException: net.minecraft.client.gui.Gui
    at gg.essential.loader.stage2.relaunch.RelaunchClassLoader.findClassImpl(RelaunchClassLoader.java:50)
    at gg.essential.loader.stage2.relaunch.IsolatedClassLoader.loadClass(IsolatedClassLoader.java:78)
    ... 55 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.client.gui.Gui
    at gg.essential.loader.stage2.relaunch.RelaunchClassLoader.findClassImpl(RelaunchClassLoader.java:33)
    ... 56 more


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at gg.essential.loader.stage2.relaunch.RelaunchClassLoader.findClassImpl(RelaunchClassLoader.java:71)
    at gg.essential.loader.stage2.relaunch.IsolatedClassLoader.loadClass(IsolatedClassLoader.java:78)
    at org.apache.logging.log4j.core.impl.ThrowableProxy.loadClass(ThrowableProxy.java:459)
    at org.apache.logging.log4j.core.impl.ThrowableProxy.resolvePackageData(ThrowableProxy.java:395)
    at org.apache.logging.log4j.core.impl.ThrowableProxy.<init>(ThrowableProxy.java:97)
    at org.apache.logging.log4j.core.impl.Log4jLogEvent.<init>(Log4jLogEvent.java:114)
    at org.apache.logging.log4j.core.impl.Log4jLogEvent.<init>(Log4jLogEvent.java:90)
    at org.apache.logging.log4j.core.impl.DefaultLogEventFactory.createEvent(DefaultLogEventFactory.java:49)
    at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:365)
    at org.apache.logging.log4j.core.Logger.log(Logger.java:110)
    at org.apache.logging.log4j.spi.AbstractLogger.log(AbstractLogger.java:1448)
    at net.minecraftforge.fml.relauncher.FMLRelaunchLog.log(FMLRelaunchLog.java:83)
    at net.minecraftforge.fml.common.FMLLog.log(FMLLog.java:40)
    at net.minecraftforge.fml.common.LoadController.transition(LoadController.java:138)
    at net.minecraftforge.fml.common.Loader.preinitializeMods(Loader.java:559)
    at net.minecraftforge.fml.client.FMLClientHandler.beginMinecraftLoading(FMLClientHandler.java:243)
    at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:417)

-- Initialization --
Details:
Stacktrace:
    at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:329)
    at net.minecraft.client.main.Main.main(SourceFile:124)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at gg.essential.loader.stage2.relaunch.Relaunch.relaunch(Relaunch.java:124)
    at gg.essential.loader.stage2.EssentialLoader.addToClasspath(EssentialLoader.java:92)
    at gg.essential.loader.stage2.EssentialLoaderBase.addToClasspath(EssentialLoaderBase.java:328)
    at gg.essential.loader.stage2.EssentialLoaderBase.load(EssentialLoaderBase.java:143)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at gg.essential.loader.stage1.EssentialLoaderBase.load(EssentialLoaderBase.java:110)
    at gg.essential.loader.stage1.EssentialSetupTweaker.<init>(EssentialSetupTweaker.java:44)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
    at gg.essential.loader.stage0.EssentialSetupTweaker.loadStage1(EssentialSetupTweaker.java:111)
    at gg.essential.loader.stage0.EssentialSetupTweaker.<init>(EssentialSetupTweaker.java:34)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
    at java.lang.Class.newInstance(Class.java:442)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:98)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

-- System Details --
Details:
    Minecraft Version: 1.8.9
    Operating System: Windows 10 (amd64) version 10.0
    Java Version: 1.8.0_51, Oracle Corporation
    Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
    Memory: 417000944 bytes (397 MB) / 771751936 bytes (736 MB) up to 2147483648 bytes (2048 MB)
    JVM Flags: 8 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
    IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
    FML: MCP 9.19 Powered by Forge 11.15.1.2318 Optifine OptiFine_1.8.9_HD_U_L5 11 mods loaded, 11 mods active
    States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored

    | State | ID                   | Version      | Source                                |
    | ----- | -------------------- | ------------ | ------------------------------------- |
    | UCH   | mcp                  | 9.19         | minecraft.jar                         |
    | UCH   | FML                  | 8.0.99.99    | forge-1.8.9-11.15.1.2318-1.8.9.jar    |
    | UCH   | Forge                | 11.15.1.2318 | forge-1.8.9-11.15.1.2318-1.8.9.jar    |
    | UCH   | essential            | 1.0.0        | Essential (forge_1.8.9).jar           |
    | UCH   | apec                 | 1.10.1       | Apec-1.10.1.jar                       |
    | UCH   | dungeonrooms         | 3.3.1        | Dungeon_Rooms-3.3.1.jar               |
    | UCE   | notenoughupdates     | 2.0.0-REL    | NotEnoughUpdates-2.0.0.jar            |
    | UCH   | orangesimplemod      | 1.0          | Orange's+Simple+Mods-1.2.jar          |
    | UCH   | text_overflow_scroll | 1.4.0        | Scrollable Tooltips-1.4 (1.8.9).jar   |
    | UCH   | skyblockaddons       | 1.5.5        | SkyblockAddons-1.5.5-for-MC-1.8.9.jar |
    | UCH   | skytils              | 1.1.2        | Skytils-1.1.2.jar                     |

    Loaded coremods (and transformers): 
Skytils On Top (Skytils-1.1.2.jar)
  skytils.skytilsmod.asm.SkytilsTransformer
SkyblockAddonsLoadingPlugin (SkyblockAddons-1.5.5-for-MC-1.8.9.jar)
  codes.biscuit.skyblockaddons.tweaker.SkyblockAddonsTransformer
FMLLoadingPlugin (Scrollable Tooltips-1.4 (1.8.9).jar)
  club.sk1er.mods.scrollabletooltips.forge.ClassTransformer
    GL info: ' Vendor: 'Intel' Version: '4.6.0 - Build 27.20.100.8984' Renderer: 'Intel(R) UHD Graphics'
    Skytils Debug Info: {HasBetterFPS=false, BetterFPS Version=NONE, Disabled Start Checks=false}
    Launched Version: 1.8.9-forge1.8.9-11.15.1.2318-1.8.9
    LWJGL: 2.9.4
    OpenGL: Intel(R) UHD Graphics GL version 4.6.0 - Build 27.20.100.8984, Intel
    GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

    Using VBOs: Yes
    Is Modded: Definitely; Client brand changed to 'fml,forge'
    Type: Client (map_client.txt)
    Resource Packs: ! §a§lVerdant §8§732x.zip
    Current Language: English (US)
    Profiler Position: N/A (disabled)
    CPU: 8x Intel(R) Core(TM) i5-10210U CPU @ 1.60GHz
    OptiFine Version: OptiFine_1.8.9_HD_U_L5
    OptiFine Build: 20191204-143016
    Render Distance Chunks: 8
    Mipmaps: 4
    Anisotropic Filtering: 1
    Antialiasing: 0
    Multitexture: false
    Shaders: null
    OpenGlVersion: 4.6.0 - Build 27.20.100.8984
    OpenGlRenderer: Intel(R) UHD Graphics
    OpenGlVendor: Intel
    CpuCount: 8

I cannot boot up my Forge client (1.8), please help me as I do not know what to do.

Guest
This topic is now closed to further replies.
https://forums.minecraftforge.net/topic/109393-forge-crash-javalangnoclassdeffounderror/
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