Problem With New Beginnings 1.5.0 Server

[Zorro00141]

Im trying to run a server using the files that were provided one the forge website for the modpack. But im getting this error when I try and connect to it. "java.lang.ClassCastException: net.minecraft.world.biome.Biome$category cannot be cast to java.lang.String" Here is the log file.

The server also shows up as a vanilla minecraft server where you would join the server. I have tried deleting and restarting the server, reinstalling curseforge and even reinstalling minecraft. None of that helped. This issue started after I created a Pixlemon server. 

Edited April 20, 2021 by Zorro00141

[Zorro00141]

I'm starting the server using the jar provided in the folder for the server.

[Zorro00141]

Im not sure what you mean, because to start the server normally I just run this one jar.

[Ugdhar]

That is the vanilla server jar, you don't run that one.

You should be running the forge jar.