I am wanting to set up a modded minecraft server for a couple of people. I set up a vanilla server and it worked fine, but when I added mods to the mods folder, it wouldnt load fully. When running the json file to launch the server, it crashes. Heres what it says when it loads up:

Spoiler

[20:27:07] [Server thread/ERROR] [FML]: The following problems were captured during this phase
[20:27:07] [Server thread/ERROR] [FML]: Caught exception from runicdungeons
java.lang.IllegalArgumentException: Failed to register dimension for id -34, One is already registered
        at net.minecraftforge.common.DimensionManager.registerDimension(DimensionManager.java:118) ~[DimensionManager.class:?]
        at mrcomputerghost.runicdungeons.RunicDungeons.preInit(RunicDungeons.java:150) ~[RunicDungeons.class:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_251]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_251]
        at cpw.mods.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:532) ~[FMLModContainer.class:?]
        at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source) ~[?:?]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_251]
        at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.post(EventBus.java:275) ~[guava-17.0.jar:?]
        at cpw.mods.fml.common.LoadController.sendEventToModContainer(LoadController.java:212) ~[LoadController.class:?]
        at cpw.mods.fml.common.LoadController.propogateStateMessage(LoadController.java:190) ~[LoadController.class:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_251]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_251]
        at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.post(EventBus.java:275) ~[guava-17.0.jar:?]
        at cpw.mods.fml.common.LoadController.distributeStateMessage(LoadController.java:119) [LoadController.class:?]
        at cpw.mods.fml.common.Loader.preinitializeMods(Loader.java:556) [Loader.class:?]
        at cpw.mods.fml.server.FMLServerHandler.beginServerLoading(FMLServerHandler.java:88) [FMLServerHandler.class:?]
        at cpw.mods.fml.common.FMLCommonHandler.onServerStart(FMLCommonHandler.java:314) [FMLCommonHandler.class:?]
        at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:117) [lt.class:?]
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:387) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685) [li.class:?]
[20:27:07] [Server thread/ERROR]: Encountered an unexpected exception
java.lang.IllegalArgumentException: Failed to register dimension for id -34, One is already registered
        at net.minecraftforge.common.DimensionManager.registerDimension(DimensionManager.java:118) ~[DimensionManager.class:?]
        at mrcomputerghost.runicdungeons.RunicDungeons.preInit(RunicDungeons.java:150) ~[RunicDungeons.class:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_251]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_251]
        at cpw.mods.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:532) ~[FMLModContainer.class:?]
        at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source) ~[?:?]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_251]
        at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.post(EventBus.java:275) ~[guava-17.0.jar:?]
        at cpw.mods.fml.common.LoadController.sendEventToModContainer(LoadController.java:212) ~[LoadController.class:?]
        at cpw.mods.fml.common.LoadController.propogateStateMessage(LoadController.java:190) ~[LoadController.class:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_251]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_251]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_251]
        at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304) ~[guava-17.0.jar:?]
        at com.google.common.eventbus.EventBus.post(EventBus.java:275) ~[guava-17.0.jar:?]
        at cpw.mods.fml.common.LoadController.distributeStateMessage(LoadController.java:119) ~[LoadController.class:?]
        at cpw.mods.fml.common.Loader.preinitializeMods(Loader.java:556) ~[Loader.class:?]
        at cpw.mods.fml.server.FMLServerHandler.beginServerLoading(FMLServerHandler.java:88) ~[FMLServerHandler.class:?]
        at cpw.mods.fml.common.FMLCommonHandler.onServerStart(FMLCommonHandler.java:314) ~[FMLCommonHandler.class:?]
        at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:117) ~[lt.class:?]
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:387) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685) [li.class:?]
[20:27:07] [Server thread/ERROR]: This crash report has been saved to: C:\Users\wmfor\Desktop\Server\.\crash-reports\crash-2020-05-11_20.27.07-server.txt
[20:27:07] [Server thread/WARN] [FML]: Can't revert to frozen GameData state without freezing first.
[20:27:07] [Server thread/INFO] [FML]: Applying holder lookups
[20:27:07] [Server thread/INFO] [FML]: Holder lookups applied
[20:27:07] [Server thread/WARN] [EnderIO]: Failed to write Transciever Channels on exit: java.util.concurrent.ExecutionException: java.lang.NullPointerException
[20:27:07] [Server thread/ERROR] [FTBU]: Skipping event FMLServerStoppedEvent and marking errored mod FTBU since required dependency FTBL has errored
[20:27:08] [Server thread/INFO] [mcjty.lib.varia.Logging]: RFTools: server is stopping. Shutting down gracefully
[20:27:08] [Server thread/INFO] [FML]: The state engine was in incorrect state ERRORED and forced into state SERVER_STOPPED. Errors may have been discarded.
[20:27:08] [Server thread/INFO] [FML]: The state engine was in incorrect state ERRORED and forced into state AVAILABLE. Errors may have been discarded.

I have had an issue where the item id is a duplicate from another mod, so I noticed the -34 id number and changed it, and the server booted up. But when I tried to log on from a client computer, I get the error message "Fatally missing blocks or items". Is there any way I can fix this or am I out of luck? Any information would be greatly appreciated. Thank you for your time and have a great day!

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