Affected Versions (Do not use "latest")::

• ArmorPlus: 11.12.1.39
• TheDragonLib: 5.2.0
• Minecraft: 1.12.2
• Forge: 14.23.4.2708
• (Optional) Just Enough Items (JEI): v 1.0.0
• (Optional) Tinkers' Construct: 2.9.1.65
• (Optional) CraftTweaker (CrT): CT2 4.1.8

Affected Side (Client or Server):

• Client
• Server

What happens: When I entered the nether I got this crash, and then when I exited and reopened the game, then started the world, I got the same exact crash.

What you expected to happen:: To enter the nether, and to re-enter into the nether

If its a crash, post your crash report (via. pastebin/gist/etc): https://pastebin.com/tbaYwHgQ

Your configuration files from config/armorplus/ (registry.cfg mainly): https://pastebin.com/RyVizza2, worldgen: https://pastebin.com/fbNKz6RE

(Optional) Mod List:

Small suggestion related to this issue for the devs, maybe add the value of minHeight and maxHeight in the exception thrown here, makes it easier to debug.
https://github.com/TheDragonTeam/ArmorPlus/blob/d932701b6a38697417e8fcb6393fd918bd4e4520/src/main/java/net/thedragonteam/armorplus/util/WorldGenUtils.java#L34

Hello, thanks for the issue report.
Could you try the following things:

• Attempt to load the world without HammerCore (if possible)
• Provide me the worldgen.cfg config file

Meanwhile, your armorplus version is outdated. newest one is ArmorPlus 1.12.2-11.13.0.40 (May 16, 2018)

Tried it without HammerCore and came back with the same crash, and I had updated ArmorPlus

Could you link the crash ? Because it cannot be the same crash. but might help resolving the issue.

Crash w/o HammerCore: https://pastebin.com/VQe0jFkT

Alrighty, now I need your worldgen.cfg inside config/armorplus. The height value seems to have been changed to an unacceptable value. minHeight must be greater than 0 and not greater than maxHeight, while maxHeight must not be greater than 256.

I posted the config in the first comment, but just in case it didn't show up, here it is: https://pastebin.com/fbNKz6RE

Well, here is your issue, thats a big nono xD

WOAH! I must have accidentally set that. Thanks! I never expected this to get answered in the same day, and now it's fixed! Thanks for your quick response.

Happy to help ^^