Startup Issue with Minecraft - Pixelmon Modpack Crash on Startup

[daniel-redder]

System Information

Field	Value
Operating System	Linux - Debian GNU/Linux 12 on x86_64
Product	AMP ‘Callisto’ v2.5.1.8 (Mainline)
Virtualization	Docker
Application	Minecraft
Module	MinecraftModule
Running in Container	Yes
Current State	Failed

Problem Description

Issue

I’m getting failure to boot. It throws a java exception immediately on boot.

Exception in thread "main" java.lang.IllegalAccessError: class cpw.mods.modlauncher.SecureJarHandler (in unnamed module @0x5b8bc155) cannot access class sun.security.util.ManifestEntryVerifier (in module java.base) because module java.base does not export sun.security.util to unnamed module @0x5b8bc155

Reproduction Steps

• Create new Minecraft Instance
• Switch to Forge in minecraft settings.
• Switch to the Jar matching the server download of “the Pixelmon modpack” 36.2.35 Jar
• Download and unzip the pixelmon modpack server link from curseforge
• Copy the contents of mods from the unzipped folder into the mods folder in the minecraft instance.

[ThePotatoKing]

You need to be using Java 8 or Java 11 for 1.16.5

[daniel-redder]

I tried this How do I change which Java version AMP uses?, but I don’t see it listed as a option in search.

If this wasn’t docker based I would know how to switch it on host.

It is in Instance/Configuration/Minecraft/Java and Memory/Java Version rather than being a instance independent setting.

[ThePotatoKing]

It depends on the instance yeah, since you can have multiple minecraft servers running requiring different Java versions