Woovie

Understood, thank you. Adding that to the documentation page would be great, just something simple stating that. I appreciate the fast reply.

I cannot find clear guidance in your documentation, so I'm posting here. Here's my environment, currently hosting a Spigot 1.13.x server, trying to add a Forge server as well under another user. [root@minecraft ~]# java --version java 11.0.2 2019-01-15 LTS Java(TM) SE Runtime Environment 18.9 (build 11.0.2+9-LTS) Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11.0.2+9-LTS, mixed mode) [root@minecraft ~]# free -m total used free shared buff/cache available Mem: 15885 5986 611 5 9287 9064 Swap: 2047 40 2007 [root@minecraft ~]# nproc 4 Attempting to start 1.12 [sevtech@minecraft forge-1.12]$ java -jar forge-1.12.2-14.23.5.2836-universal.jar 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(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:566) at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.java:70) at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.java:34) Caused by: java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to class java.net.URLClassLoader (jdk.internal.loader.ClassLoaders$AppClassLoader and java.net.URLClassLoader are in module java.base of loader 'bootstrap') at net.minecraft.launchwrapper.Launch.<init>(Launch.java:34) at net.minecraft.launchwrapper.Launch.main(Launch.java:28) ... 6 more And attempting 1.13 [sevtech@minecraft forge-1.13]$ java -jar forge-1.13.2-25.0.135.jar [20:05:33.168] [main/INFO] [Launcher/MODLAUNCHER]: ModLauncher running: args [--gameDir, ., --launchTarget, fmlserver, --fml.forgeVersion, 25.0.135, --fml.mcpVersion, 20190213.203750, --fml.mcVersion, 1.13.2, --fml.forgeGroup, net.minecraftforge] [20:05:33.170] [main/INFO] [Launcher/MODLAUNCHER]: ModLauncher starting: java version 11.0.2 [20:05:33.304] [main/INFO] [loading.FixSSL/CORE]: Added Lets Encrypt root certificates as additional trust [20:05:33.729] [main/INFO] [LaunchServiceHandler/MODLAUNCHER]: Launching target 'fmlserver' with arguments [--gameDir, .] Exception in thread "main" java.lang.RuntimeException: java.lang.UnsupportedOperationException at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:21) at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:32) at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:50) at cpw.mods.modlauncher.Launcher.run(Launcher.java:57) at cpw.mods.modlauncher.Launcher.main(Launcher.java:43) at net.minecraftforge.server.ServerMain$Runner.runLauncher(ServerMain.java:63) at net.minecraftforge.server.ServerMain$Runner.access$100(ServerMain.java:60) at net.minecraftforge.server.ServerMain.main(ServerMain.java:57) Caused by: java.lang.UnsupportedOperationException at org.objectweb.asm.ClassVisitor.visitNestMemberExperimental(ClassVisitor.java:248) at org.objectweb.asm.ClassReader.accept(ClassReader.java:651) at org.objectweb.asm.ClassReader.accept(ClassReader.java:391) at cpw.mods.modlauncher.TransformerClassWriter.computeHierarchy(TransformerClassWriter.java:65) at cpw.mods.modlauncher.TransformerClassWriter.getSupers(TransformerClassWriter.java:36) at cpw.mods.modlauncher.TransformerClassWriter.getCommonSuperClass(TransformerClassWriter.java:81) at org.objectweb.asm.SymbolTable.addMergedType(SymbolTable.java:1209) at org.objectweb.asm.Frame.merge(Frame.java:1293) at org.objectweb.asm.Frame.merge(Frame.java:1175) at org.objectweb.asm.MethodWriter.computeAllFrames(MethodWriter.java:1604) at org.objectweb.asm.MethodWriter.visitMaxs(MethodWriter.java:1540) at org.objectweb.asm.tree.MethodNode.accept(MethodNode.java:807) at org.objectweb.asm.tree.MethodNode.accept(MethodNode.java:687) at org.objectweb.asm.tree.ClassNode.accept(ClassNode.java:436) at cpw.mods.modlauncher.ClassTransformer.transform(ClassTransformer.java:96) at cpw.mods.modlauncher.TransformingClassLoader$DelegatedClassLoader.findClass(TransformingClassLoader.java:214) at cpw.mods.modlauncher.TransformingClassLoader.loadClass(TransformingClassLoader.java:76) at cpw.mods.modlauncher.TransformingClassLoader$DelegatedClassLoader.loadClass(TransformingClassLoader.java:169) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.getDeclaredMethods0(Native Method) at java.base/java.lang.Class.privateGetDeclaredMethods(Class.java:3167) at java.base/java.lang.Class.getMethodsRecursive(Class.java:3308) at java.base/java.lang.Class.getMethod0(Class.java:3294) at java.base/java.lang.Class.getMethod(Class.java:2107) at net.minecraftforge.fml.loading.FMLServerLaunchProvider.lambda$launchService$0(FMLServerLaunchProvider.java:50) at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:19) ... 7 more Not seeing any clear indicators as to why either are failing, I'm also not familiar with debugging Java or reading a Java error stack. Any support is appreciated.