We appear to be missing one or more essential library files

[CatGentleman235]

Hi I made a server It worked 2-3 weeks but after it says : We appear to be missing one or more essential library files.
You will need to add them to your server before FML and Forge will run successfully.java.lang.ClassNotFoundException: net.minecraft.launchwrapper.Launch
        at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source). I am using MyMcAdmin it was working but Its now dead. There is the log of my software.

[ichttt]

Launchwrapper(which is a required library for forge) does not support java 9, please use java 8.

[CatGentleman235]

On 29/10/2017 at 5:14 PM, ichttt said:

Launchwrapper(which is a required library for forge) does not support java 9, please use java 8.

It's working! Thank you!