


Previously the only way to avoid this crash was to downgrade to Java 7 or an older version of Java 8, however LexManos has released the Legacy Java Fixer coremod that fixes these bugs at runtime and makes old Forge versions once again compatible with current Java versions. This makes most old modpacks crash before even attempting to load most mods. Technical Details This crash is caused by a bug in numerous old versions of Minecraft Forge notably those for Minecraft 1. If not, please start a new threadupload your console log and link to it in your post. The Legacy Java Fixer will solve your crash most of the time. If you want to install the mod using the launcher, make sure to choose Mods Folder as the mod type.

ConcurrentModificationException", there is a very easy fix: Download the Legacy Java Fixer mod and place it into the mods folder of your instance or server. If you're using an old modpack older than Minecraft 1. This fix is only needed for old modpacks using Minecraft 1. If you wish to get support or talk with other community members, please use our Discord server here. You will no longer be able to post in these forums.
