The game crashes at startup and the launcher gives the following error message:
Error: java.lang.IllegalArgumentException

Expected behavior
The game should not crash.

Environment
No other mods are installed and the crash happened at a SP environment.
System: Windows 10 64-bit
Java 8 Update 191 (64 bit)

• Minecraft Version: 1.12.2
• AE2 Version: rv-6-stable-6
• Forge Version: 1.12.2-14.23.5.2768

Crash-Report: https://pastebin.com/CMRU6Axe
latest Log: https://pastebin.com/SdYRB2HE

This error also happend with the versions rv-6stable-3 until rv-6-stable-5.

Any help is appreciated

A wild guess would be, you disabled channels and you tried using custom recipes and still have items in it that disappeared due to disabled channels. To be precise you crash on loading the recipe for the controller

Well,
I removed the custom recipes by removing the corresponding .zs file from the scripts folder.
So every recipe should be the regular one.
Enabling channels in the config still got me a crash. Here it is:
https://pastebin.com/ZNGp20Zq
And also the custom recipes worked with version rv-6-stable-2

AE got his own recipe files, can you check if those are enabled too? Sorry did not play mc for a while yet because of holidays, so can not tell you the exact option

There are several .recipe files in config\AppliedEnergistics2\aerecipes but there is no option to enable/disable anything. So I suppose you meant WebsiteRecipes in the .cfg file.
It was disabled but enabling it didn't change anything. Still the same crash.
https://pastebin.com/WpKsu8Kq

@yueh did something change in the recipe system that may explain this behaviour with disabled channels? someone or something makes AE crash on the recipe checks because of an illegal null pointer in the silicon smelting and there is an recipe for the controller present but the controller is disabled

I fixed it.
The silicon you mentioned got me the idea. For whatever reason the option "silicon" under materials in the cfg-file was disabled. Enabling it fixed everything. Now I just need to test, whether this works with ender-io since that mod also adds silicon.
Thank you for your help :D

Duplicate of #3850