Ruen

Here are the key issues visible in the log: ⚠️ “Incomplete set of tags” error → This usually means the server and client don’t agree on the registry of blocks/items. Some mods are failing to register their tags properly, so the client sees missing definitions. ⚠️ ClassNotFound errors → Several mods (e.g., Biomes O’ Plenty, Dynamic Trees, Dark Utilities, Corpse/Gravestone) are throwing ClassNotFoundException. That indicates the server is missing required mod files or they weren’t loaded correctly. ⚠️ Reference map errors → Multiple mixin reference maps (eidolonrecipes.refmap.json, nethers_delight.refmap.json, etc.) couldn’t be read. While not always fatal, they point to mods not being fully initialized. ⚠️ Potentially Dangerous alternative prefix warnings → Mods like Rats are registering items under unexpected namespaces (rats:block_of_cheese instead of minecraft:block_of_cheese). These mismatches can break tag validation. ⚠️ Modpack reinstall didn’t fix it → Since both client and server were reinstalled but the issue persists, it suggests either: The server is missing certain mods compared to the client. The modpack installation didn’t fully sync configs/datapacks. A corrupted datapack or recipe file is breaking tag loading. 👉 In short: the inability to join is caused by mod mismatches between client and server, specifically missing classes and broken tag registries. The fix would be to carefully verify that the exact same modpack version (including configs and datapacks) is installed on both sides, and check for mods that failed to copy into the server’s mods/ folder.