Warning
A required class is missing
NoClassDefFoundError / ClassNotFoundException — fix mod conflicts
Example error line
java.lang.NoClassDefFoundError: some/Mod/Class
Cause
A required class is missing — a mod/plugin expects another mod or a different version that is not installed.
Fix
Learn more
Check the mod/plugin's dependencies and versions; install the missing dependency or a matching build.
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Minecraft Java · Configure nowRelated errors
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