Hi, I am trying to start a server for me an my friends. And I am not exactly sure why the server is not able to start. I have followed some guides to get a server started but I keep getting this crash log. If anyone can provide some direction that would be great. Thank you!

[00:14:33] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLServerTweaker
[00:14:33] [main/INFO] [LaunchWrapper]: Using primary tweak class name net.minecraftforge.fml.common.launcher.FMLServerTweaker
[00:14:33] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLServerTweaker
[00:14:33] [main/INFO] [FML]: Forge Mod Loader version 14.23.5.2854 for Minecraft 1.12.2 loading
[00:14:33] [main/INFO] [FML]: Java is Java HotSpot(TM) 64-Bit Server VM, version 1.8.0_301, running on Windows 10:amd64:10.0, installed at C:\Program Files\Java\jre1.8.0_301
[00:14:33] [main/INFO] [FML]: Searching C:\Users\GamaR\Desktop\Pixelmon Server\.\mods for mods
[00:14:33] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[00:14:33] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLDeobfTweaker
[00:14:33] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[00:14:33] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLInjectionAndSortingTweaker
[00:14:33] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.relauncher.CoreModManager$FMLPluginWrapper
[00:14:34] [main/INFO] [FML]: Found valid fingerprint for Minecraft Forge. Certificate fingerprint e3c3d50c7c986df74c645c0ac54639741c90a557
[00:14:34] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.relauncher.CoreModManager$FMLPluginWrapper
[00:14:34] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.FMLDeobfTweaker
[00:14:34] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.fml.common.launcher.TerminalTweaker
[00:14:34] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.fml.common.launcher.TerminalTweaker
[00:14:34] [main/INFO] [LaunchWrapper]: Launching wrapped minecraft {net.minecraft.server.MinecraftServer}
[00:14:36] [Server thread/INFO] [net.minecraft.server.dedicated.DedicatedServer]: Starting minecraft server version 1.12.2
[00:14:36] [Server thread/INFO] [FML]: MinecraftForge v14.23.5.2854 Initialized
[00:14:36] [Server thread/INFO] [FML]: Starts to replace vanilla recipe ingredients with ore ingredients.
[00:14:36] [Server thread/INFO] [FML]: Invalid recipe found with multiple oredict ingredients in the same ingredient...
[00:14:36] [Server thread/INFO] [FML]: Replaced 1227 ore ingredients
[00:14:36] [Server thread/INFO] [FML]: Searching C:\Users\GamaR\Desktop\Pixelmon Server\.\mods for mods
[00:14:37] [Server thread/WARN] [FML]: Mod fancymenu is missing the required element 'version' and a version.properties file could not be found. Falling back to metadata version 1.5.2
[00:14:37] [Server thread/WARN] [FML]: Mod konkrete is missing the required element 'version' and a version.properties file could not be found. Falling back to metadata version 1.0.3
[00:14:37] [Server thread/INFO] [FML]: Forge Mod Loader has identified 12 mods to load
[00:14:37] [Server thread/WARN] [FML]: Missing English translation for FML: assets/fml/lang/en_us.lang
[00:14:37] [Server thread/WARN] [FML]: Missing English translation for bop_patch: assets/bop_patch/lang/en_us.lang
[00:14:37] [Server thread/WARN] [FML]: Missing English translation for fancymenu: assets/fancymenu/lang/en_us.lang
[00:14:37] [Server thread/WARN] [FML]: Missing English translation for konkrete: assets/konkrete/lang/en_us.lang
[00:14:37] [Server thread/INFO] [FML]: Attempting connection with missing mods [minecraft, mcp, FML, forge, biomesoplenty, bop_patch, fancymenu, gameshark, journeymap, konkrete, naturescompass, pixelmon] at CLIENT
[00:14:37] [Server thread/INFO] [FML]: Attempting connection with missing mods [minecraft, mcp, FML, forge, biomesoplenty, bop_patch, fancymenu, gameshark, journeymap, konkrete, naturescompass, pixelmon] at SERVER
[00:14:38] [Server thread/ERROR] [net.minecraft.server.MinecraftServer]: Encountered an unexpected exception
java.lang.NoClassDefFoundError: net/minecraft/server/integrated/IntegratedServer
    at de.keksuccino.konkrete.Konkrete.<init>(Konkrete.java:23) ~[Konkrete.class:?]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_301]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_301]
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_301]
    at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[?:1.8.0_301]
    at java.lang.Class.newInstance(Unknown Source) ~[?:1.8.0_301]
    at net.minecraftforge.fml.common.ILanguageAdapter$JavaAdapter.getNewInstance(ILanguageAdapter.java:191) ~[forgeserver.jar:?]
    at net.minecraftforge.fml.common.FMLModContainer.constructMod(FMLModContainer.java:599) ~[forgeserver.jar:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_301]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_301]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_301]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_301]
    at com.google.common.eventbus.Subscriber.invokeSubscriberMethod(Subscriber.java:91) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.Subscriber$SynchronizedSubscriber.invokeSubscriberMethod(Subscriber.java:150) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.Subscriber$1.run(Subscriber.java:76) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.util.concurrent.MoreExecutors$DirectExecutor.execute(MoreExecutors.java:399) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.Subscriber.dispatchEvent(Subscriber.java:71) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.Dispatcher$PerThreadQueuedDispatcher.dispatch(Dispatcher.java:116) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.EventBus.post(EventBus.java:217) ~[minecraft_server.1.12.2.jar:?]
    at net.minecraftforge.fml.common.LoadController.sendEventToModContainer(LoadController.java:219) ~[forgeserver.jar:?]
    at net.minecraftforge.fml.common.LoadController.propogateStateMessage(LoadController.java:197) ~[forgeserver.jar:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_301]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_301]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_301]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_301]
    at com.google.common.eventbus.Subscriber.invokeSubscriberMethod(Subscriber.java:91) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.Subscriber$SynchronizedSubscriber.invokeSubscriberMethod(Subscriber.java:150) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.Subscriber$1.run(Subscriber.java:76) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.util.concurrent.MoreExecutors$DirectExecutor.execute(MoreExecutors.java:399) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.Subscriber.dispatchEvent(Subscriber.java:71) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.Dispatcher$PerThreadQueuedDispatcher.dispatch(Dispatcher.java:116) ~[minecraft_server.1.12.2.jar:?]
    at com.google.common.eventbus.EventBus.post(EventBus.java:217) ~[minecraft_server.1.12.2.jar:?]
    at net.minecraftforge.fml.common.LoadController.distributeStateMessage(LoadController.java:136) ~[LoadController.class:?]
    at net.minecraftforge.fml.common.Loader.loadMods(Loader.java:595) ~[Loader.class:?]
    at net.minecraftforge.fml.server.FMLServerHandler.beginServerLoading(FMLServerHandler.java:98) ~[FMLServerHandler.class:?]
    at net.minecraftforge.fml.common.FMLCommonHandler.onServerStart(FMLCommonHandler.java:333) ~[FMLCommonHandler.class:?]
    at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:125) ~[nz.class:?]
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:486) [MinecraftServer.class:?]
    at java.lang.Thread.run(Unknown Source) [?:1.8.0_301]
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.integrated.IntegratedServer
    at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191) ~[launchwrapper-1.12.jar:?]
    at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_301]
    at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_301]
    ... 39 more
Caused by: net.minecraftforge.fml.common.asm.ASMTransformerWrapper$TransformerException: Exception in class transformer net.minecraftforge.fml.common.asm.transformers.SideTransformer@7d151a from coremod FMLCorePlugin
    at net.minecraftforge.fml.common.asm.ASMTransformerWrapper$TransformerWrapper.transform(ASMTransformerWrapper.java:260) ~[forgeserver.jar:?]
    at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) ~[launchwrapper-1.12.jar:?]
    at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) ~[launchwrapper-1.12.jar:?]
    at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_301]
    at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_301]
    ... 39 more
Caused by: java.lang.RuntimeException: Attempted to load class chd for invalid side SERVER
    at net.minecraftforge.fml.common.asm.transformers.SideTransformer.transform(SideTransformer.java:62) ~[forgeserver.jar:?]
    at net.minecraftforge.fml.common.asm.ASMTransformerWrapper$TransformerWrapper.transform(ASMTransformerWrapper.java:256) ~[forgeserver.jar:?]
    at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) ~[launchwrapper-1.12.jar:?]
    at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) ~[launchwrapper-1.12.jar:?]
    at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_301]
    at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_301]
    ... 39 more
[00:14:38] [Server thread/ERROR] [net.minecraft.server.MinecraftServer]: This crash report has been saved to: C:\Users\GamaR\Desktop\Pixelmon Server\.\crash-reports\crash-2021-10-02_00.14.38-server.txt
[00:14:38] [Server thread/INFO] [net.minecraft.server.MinecraftServer]: Stopping server
[00:14:38] [Server thread/INFO] [net.minecraft.server.MinecraftServer]: Saving worlds
[00:14:38] [Server thread/INFO] [FML]: The state engine was in incorrect state PREINITIALIZATION and forced into state SERVER_STOPPED. Errors may have been discarded.
[00:14:38] [Server Shutdown Thread/INFO] [net.minecraft.server.MinecraftServer]: Stopping server
[00:14:38] [Server Shutdown Thread/INFO] [net.minecraft.server.MinecraftServer]: Saving worlds
 

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