So... Whenever I open minecraft with forge installed I can type in the forge commands but they do nothing and when i place or remove a block the game crashes. I tried this on 3 versions of forge, the latest 1.15.2 - 31.1.44, the recommended 1.15.2 - 31.1.0, and the one before the recommended version and they all caused me the same problem.
This is the error I get, someone already posted the same error but somehow solved it.
Thx for the help.
---- Minecraft Crash Report ----
// Daisy, daisy...
Time: 14.04.20 18:58
Description: Exception in server tick loop
java.lang.NoClassDefFoundError: net/minecraft/world/gen/feature/BigTreeFeature
at com.sk89q.worldedit.forge.ForgeWorldEdit.getWorld(ForgeWorldEdit.java:315) ~[?:?] {re:classloading}
at com.sk89q.worldedit.forge.ForgeWorldEdit.onPlayerInteract(ForgeWorldEdit.java:236) ~[?:?] {re:classloading}
at net.minecraftforge.eventbus.ASMEventHandler_5_ForgeWorldEdit_onPlayerInteract_PlayerInteractEvent.invoke(.dynamic) ~[?:?] {}
at net.minecraftforge.eventbus.ASMEventHandler.invoke(ASMEventHandler.java:80) ~[eventbus-2.0.0-milestone.1-service.jar:?] {}
at net.minecraftforge.eventbus.EventBus.post(EventBus.java:258) ~[eventbus-2.0.0-milestone.1-service.jar:?] {}
at net.minecraftforge.common.ForgeHooks.onLeftClickBlock(ForgeHooks.java:777) ~[?:?] {re:classloading}
at net.minecraft.server.management.PlayerInteractionManager.func_225416_a(PlayerInteractionManager.java:120) ~[?:?] {re:classloading}
at net.minecraft.network.play.ServerPlayNetHandler.func_147345_a(ServerPlayNetHandler.java:833) ~[?:?] {re:classloading}
at net.minecraft.network.play.client.CPlayerDiggingPacket.func_148833_a(SourceFile:40) ~[?:?] {re:classloading}
at net.minecraft.network.play.client.CPlayerDiggingPacket.func_148833_a(SourceFile:10) ~[?:?] {re:classloading}
at net.minecraft.network.PacketThreadUtil.func_225383_a(SourceFile:21) ~[?:?] {re:classloading}
at net.minecraft.network.PacketThreadUtil$$Lambda$4905/2026725482.run(Unknown Source) ~[?:?] {}
at net.minecraft.util.concurrent.TickDelayedTask.run(SourceFile:18) ~[?:?] {re:classloading}
at net.minecraft.util.concurrent.ThreadTaskExecutor.func_213166_h(SourceFile:144) ~[?:?] {re:classloading,pl:accesstransformer:B}
at net.minecraft.util.concurrent.RecursiveEventLoop.func_213166_h(SourceFile:23) ~[?:?] {re:classloading}
at net.minecraft.server.MinecraftServer.func_213166_h(MinecraftServer.java:729) ~[?:?] {re:classloading,pl:accesstransformer:B}
at net.minecraft.server.MinecraftServer.func_213166_h(MinecraftServer.java:141) ~[?:?] {re:classloading,pl:accesstransformer:B}
at net.minecraft.util.concurrent.ThreadTaskExecutor.func_213168_p(SourceFile:118) ~[?:?] {re:classloading,pl:accesstransformer:B}
at net.minecraft.server.MinecraftServer.func_213205_aW(MinecraftServer.java:712) ~[?:?] {re:classloading,pl:accesstransformer:B}
at net.minecraft.server.MinecraftServer.func_213168_p(MinecraftServer.java:706) ~[?:?] {re:classloading,pl:accesstransformer:B}
at net.minecraft.util.concurrent.ThreadTaskExecutor.func_213160_bf(SourceFile:103) ~[?:?] {re:classloading,pl:accesstransformer:B}
at net.minecraft.server.MinecraftServer.func_213202_o(MinecraftServer.java:691) ~[?:?] {re:classloading,pl:accesstransformer:B}
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:639) [?:?] {re:classloading,pl:accesstransformer:B}
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_51] {}
Caused by: java.lang.ClassNotFoundException: net.minecraft.world.gen.feature.BigTreeFeature
at java.lang.ClassLoader.findClass(ClassLoader.java:530) ~[?:1.8.0_51] {}
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_51] {}
at cpw.mods.modlauncher.TransformingClassLoader.loadClass(TransformingClassLoader.java:101) ~[modlauncher-5.0.0-milestone.4.jar:?] {}
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_51] {}
... 24 more
A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------
-- System Details --
Details:
Minecraft Version: 1.15.2
Minecraft Version ID: 1.15.2
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: 872526720 bytes (832 MB) / 2147483648 bytes (2048 MB) up to 2147483648 bytes (2048 MB)
CPUs: 4
JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
ModLauncher: 5.0.0-milestone.4+67+b1a340b
ModLauncher launch target: fmlclient
ModLauncher naming: srg
ModLauncher services:
/eventbus-2.0.0-milestone.1-service.jar eventbus PLUGINSERVICE
/forge-1.15.2-31.0.19.jar object_holder_definalize PLUGINSERVICE
/forge-1.15.2-31.0.19.jar runtime_enum_extender PLUGINSERVICE
/accesstransformers-2.0.0-milestone.1-shadowed.jar accesstransformer PLUGINSERVICE
/forge-1.15.2-31.0.19.jar capability_inject_definalize PLUGINSERVICE
/forge-1.15.2-31.0.19.jar runtimedistcleaner PLUGINSERVICE
/forge-1.15.2-31.0.19.jar fml TRANSFORMATIONSERVICE
FML: 31.0
Forge: net.minecraftforge:31.0.19
FML Language Providers:
javafml@31.0
minecraft@1
Mod List:
forge-1.15.2-31.0.19-client.jar Minecraft {minecraft@1.15.2 DONE}
forge-1.15.2-31.0.19-universal.jar Forge {forge@31.0.19 DONE}
worldedit-forge-mc1.14.4-7.0.1.jar WorldEdit {worldedit@7.0.1;61bc012 DONE}
Player Count: 1 / 8; [ServerPlayerEntity['_Meluna_'/211, l='Inturia', x=346.85, y=63.00, z=-425.59]]
Data Packs: vanilla, mod:forge (incompatible), mod:worldedit (incompatible)
Type: Integrated Server (map_client.txt)
Is Modded: Definitely; Client brand changed to 'forge'