Error when loading mod (NoClassDefFoundError: net/minecraft/item/Itemgroup)

[Chise986]

When opening up Minecraft Forge 1.18.1, I am met with an error stating "Error loading mods"..."1 error has occured during loading"...Ice and Fire (iceandfire) has failed to load correctly"..."java.lang.NoClassDefFoundError:net/minecraft/item/ItemGroup"

Latest Log:

[23Dec2021 15:35:41.993] [main/INFO] [cpw.mods.modlauncher.Launcher/MODLAUNCHER]: ModLauncher running: args [--username, Chise986, --version, 1.18.1-forge-39.0.8, --gameDir, C:\Users\maide\AppData\Roaming\.minecraft, --assetsDir, C:\Users\maide\AppData\Roaming\.minecraft\assets, --assetIndex, 1.18, --uuid, 262c02c2869a4b8cafdf470493a21037, --accessToken, ????????, --clientId, YjA1NzIxZjAtMTkwZi00ZDMxLTk3M2MtMGQ3OGMzODU0YjVm, --xuid, 2535438505824777, --userType, msa, --versionType, release, --launchTarget, forgeclient, --fml.forgeVersion, 39.0.8, --fml.mcVersion, 1.18.1, --fml.forgeGroup, net.minecraftforge, --fml.mcpVersion, 20211210.034407]
[23Dec2021 15:35:41.993] [main/INFO] [cpw.mods.modlauncher.Launcher/MODLAUNCHER]: ModLauncher 9.0.7+91+master.8569cdf starting: java version 17.0.1 by Microsoft
[23Dec2021 15:35:42.087] [main/INFO] [mixin/]: SpongePowered MIXIN Subsystem Version=0.8.5 Source=union:/C:/Users/maide/AppData/Roaming/.minecraft/libraries/org/spongepowered/mixin/0.8.5/mixin-0.8.5.jar%2319! Service=ModLauncher Env=CLIENT
[23Dec2021 15:35:43.316] [main/INFO] [mixin/]: Compatibility level set to JAVA_17
[23Dec2021 15:35:43.316] [main/INFO] [cpw.mods.modlauncher.LaunchServiceHandler/MODLAUNCHER]: Launching target 'forgeclient' with arguments [--version, 1.18.1-forge-39.0.8, --gameDir, C:\Users\maide\AppData\Roaming\.minecraft, --assetsDir, C:\Users\maide\AppData\Roaming\.minecraft\assets, --uuid, 262c02c2869a4b8cafdf470493a21037, --username, Chise986, --assetIndex, 1.18, --accessToken, ????????, --clientId, YjA1NzIxZjAtMTkwZi00ZDMxLTk3M2MtMGQ3OGMzODU0YjVm, --xuid, 2535438505824777, --userType, msa, --versionType, release]
[23Dec2021 15:35:43.444] [main/WARN] [mixin/]: Error loading class: net/minecraft/world/gen/feature/LakesFeature (java.lang.ClassNotFoundException: net.minecraft.world.gen.feature.LakesFeature)
[23Dec2021 15:35:43.444] [main/WARN] [mixin/]: @Mixin target net.minecraft.world.gen.feature.LakesFeature was not found iceandfire.mixins.json:NoLakesInStructuresMixin
[15:35:50] [Render thread/WARN]: Assets URL 'union:/C:/Users/maide/AppData/Roaming/.minecraft/libraries/net/minecraft/client/1.18.1-20211210.034407/client-1.18.1-20211210.034407-srg.jar%2354!/assets/.mcassetsroot' uses unexpected schema
[15:35:50] [Render thread/WARN]: Assets URL 'union:/C:/Users/maide/AppData/Roaming/.minecraft/libraries/net/minecraft/client/1.18.1-20211210.034407/client-1.18.1-20211210.034407-srg.jar%2354!/data/.mcassetsroot' uses unexpected schema
[23Dec2021 15:35:50.349] [Render thread/INFO] [com.mojang.authlib.yggdrasil.YggdrasilAuthenticationService/]: Environment: authHost='https://authserver.mojang.com', accountsHost='https://api.mojang.com', sessionHost='https://sessionserver.mojang.com', servicesHost='https://api.minecraftservices.com', name='PROD'
[15:35:51] [Render thread/INFO]: Setting user: Chise986
[15:35:51] [Render thread/INFO]: Backend library: LWJGL version 3.2.2 SNAPSHOT
[23Dec2021 15:35:55.972] [modloading-worker-0/ERROR] [net.minecraftforge.fml.javafmlmod.FMLModContainer/LOADING]: Failed to create mod instance. ModID: iceandfire, class com.github.alexthe666.iceandfire.IceAndFire
java.lang.NoClassDefFoundError: net/minecraft/item/ItemGroup
    at java.lang.Class.getDeclaredConstructors0(Native Method) ~[?:?]
    at java.lang.Class.privateGetDeclaredConstructors(Class.java:3373) ~[?:?]
    at java.lang.Class.getConstructor0(Class.java:3578) ~[?:?]
    at java.lang.Class.getDeclaredConstructor(Class.java:2754) ~[?:?]
    at net.minecraftforge.fml.javafmlmod.FMLModContainer.constructMod(FMLModContainer.java:81) ~[javafmllanguage-1.18.1-39.0.8.jar%2356!:?]
    at net.minecraftforge.fml.ModContainer.lambda$buildTransitionHandler$4(ModContainer.java:120) ~[fmlcore-1.18.1-39.0.8.jar%2355!:?]
    at java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1804) [?:?]
    at java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1796) [?:?]
    at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373) [?:?]
    at java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182) [?:?]
    at java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655) [?:?]
    at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622) [?:?]
    at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165) [?:?]
Caused by: java.lang.ClassNotFoundException: net.minecraft.item.ItemGroup
    at jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641) ~[?:?]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:520) ~[?:?]
    at cpw.mods.cl.ModuleClassLoader.loadClass(ModuleClassLoader.java:132) ~[securejarhandler-0.9.54.jar:?]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:520) ~[?:?]
    at cpw.mods.cl.ModuleClassLoader.loadClass(ModuleClassLoader.java:132) ~[securejarhandler-0.9.54.jar:?]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:520) ~[?:?]
    ... 13 more
[15:35:56] [modloading-worker-0/INFO]: Forge mod loading, version 39.0.8, for MC 1.18.1 with MCP 20211210.034407
[15:35:56] [modloading-worker-0/INFO]: MinecraftForge v39.0.8 Initialized
[23Dec2021 15:35:56.621] [Render thread/FATAL] [net.minecraftforge.fml.ModLoader/LOADING]: Failed to complete lifecycle event CONSTRUCT, 1 errors found
[23Dec2021 15:35:56.885] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.sound.SoundLoadEvent to a broken mod state
[23Dec2021 15:35:57.192] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.ColorHandlerEvent$Block to a broken mod state
[23Dec2021 15:35:57.195] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.ColorHandlerEvent$Item to a broken mod state
[23Dec2021 15:35:57.938] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.ParticleFactoryRegisterEvent to a broken mod state
[23Dec2021 15:35:58.030] [Render thread/INFO] [com.mojang.text2speech.NarratorWindows/]: Narrator library for x64 successfully loaded
[23Dec2021 15:35:58.148] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.RegisterClientReloadListenersEvent to a broken mod state
[23Dec2021 15:35:58.149] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.EntityRenderersEvent$RegisterLayerDefinitions to a broken mod state
[23Dec2021 15:35:58.150] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.EntityRenderersEvent$RegisterRenderers to a broken mod state
[15:35:58] [Render thread/INFO]: Reloading ResourceManager: Default
[23Dec2021 15:35:58.663] [Worker-Main-24/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:35:58.663] [Worker-Main-22/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:35:58.663] [Worker-Main-17/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:35:58.726] [Worker-Main-19/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.ModelRegistryEvent to a broken mod state
[23Dec2021 15:36:09.755] [Worker-Main-19/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:36:10.113] [Worker-Main-19/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:36:10.117] [Worker-Main-19/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:36:10.128] [Worker-Main-19/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:36:10.139] [Worker-Main-19/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:36:10.144] [Worker-Main-19/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[23Dec2021 15:36:10.149] [Worker-Main-19/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Pre to a broken mod state
[15:36:10] [Render thread/INFO]: OpenAL initialized on device OpenAL Soft on Speakers (BD-GH030)
[15:36:10] [Render thread/INFO]: Sound engine started
[15:36:10] [Render thread/INFO]: Created: 1024x512x4 minecraft:textures/atlas/blocks.png-atlas
[23Dec2021 15:36:10.411] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:10] [Render thread/INFO]: Created: 256x128x4 minecraft:textures/atlas/signs.png-atlas
[23Dec2021 15:36:10.412] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:10] [Render thread/INFO]: Created: 512x512x4 minecraft:textures/atlas/banner_patterns.png-atlas
[23Dec2021 15:36:10.415] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:10] [Render thread/INFO]: Created: 512x512x4 minecraft:textures/atlas/shield_patterns.png-atlas
[23Dec2021 15:36:10.417] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:10] [Render thread/INFO]: Created: 256x256x4 minecraft:textures/atlas/chest.png-atlas
[23Dec2021 15:36:10.418] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:10] [Render thread/INFO]: Created: 512x256x4 minecraft:textures/atlas/beds.png-atlas
[23Dec2021 15:36:10.419] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:10] [Render thread/INFO]: Created: 512x256x4 minecraft:textures/atlas/shulker_boxes.png-atlas
[23Dec2021 15:36:10.421] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[23Dec2021 15:36:10.635] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.ModelBakeEvent to a broken mod state
[23Dec2021 15:36:10.803] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.EntityRenderersEvent$AddLayers to a broken mod state
[23Dec2021 15:36:11.030] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.RegisterShadersEvent to a broken mod state
[15:36:11] [Render thread/INFO]: Created: 256x256x0 minecraft:textures/atlas/particles.png-atlas
[23Dec2021 15:36:11.111] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:11] [Render thread/INFO]: Created: 256x256x0 minecraft:textures/atlas/paintings.png-atlas
[23Dec2021 15:36:11.113] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:11] [Render thread/INFO]: Created: 128x128x0 minecraft:textures/atlas/mob_effects.png-atlas
[23Dec2021 15:36:11.114] [Render thread/ERROR] [net.minecraftforge.fml.ModLoader/]: Cowardly refusing to send event net.minecraftforge.client.event.TextureStitchEvent$Post to a broken mod state
[15:36:11] [Render thread/FATAL]: Preparing crash report with UUID bea3afa6-9109-4ab0-a1a1-26c77d7a41de
[15:36:11] [Render thread/FATAL]: Crash report saved to C:\Users\maide\AppData\Roaming\.minecraft\crash-reports\crash-2021-12-23_15.36.11-fml.txt
[15:36:11] [Render thread/FATAL]: Preparing crash report with UUID e92c6b4f-1034-45ba-90fc-e70fe071f98d
 

 

 

 

Help would be greatly appreciated.