C:\Users\Hayden\Desktop\Modded Server>java -Xmx2G -Xms1G -XX:MaxPermSize=128m -jar "TekkitLegends.jar" -o true nogui
Java HotSpot(TM) 64-Bit Server VM warning: Ignoring option MaxPermSize; support was removed in 8.0
A problem occurred running the Server launcher.java.lang.reflect.InvocationTargetException
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.base/java.lang.reflect.Method.invoke(Unknown Source)
        at cpw.mods.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.java:43)
        at cpw.mods.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.java:12)
Caused by: java.lang.ClassCastException: java.base/jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to java.base/java.net.URLClassLoader
        at net.minecraft.launchwrapper.Launch.<init>(Launch.java:34)
        at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
        ... 6 more

C:\Users\Hayden\Desktop\Modded Server>pause
Press any key to continue . . .