D:\Minecraft servers\LDOH>Java -Xmx12G -Xms4G -jar forge-1.12.2-14.23.5.2860.jar nogui
A problem occurred running the Server launcher.java.lang.reflect.InvocationTargetException
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:110)
        at java.base/java.lang.reflect.Method.invoke(Method.java:577)
        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)
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
        ... 3 more

D:\Minecraft servers\LDOH>pause
Press any key to continue . . .

I have created a path for java 8, using environment variables, this did not work and the topic was locked before I could respond. I can run the normal minecraft server but cant the forge. I've done my own research before this and nothing seems to work. I have fixed these issues before, but this time i cannot.

I did lock the thread, but I also know that the java version being used right now is not Java 8 purely by the report given. So show what you have done with the environment variables including the path.