An item with the same key has already been added. Key: ReloadMP

[Laurenssssssss]

Hero’s Mod is trying to register the same hotkey/action twice, probably during multiplayer/server world loading. This is a known issue in mods that aren't updated properly for newer tModLoader versions or conflict with other mods.

Exactly — all signs point to Hero’s Mod being the cause:

✔️ Works fine without it

❌ Throws ArgumentException: An item with the same key has already been added when enabled

🔁 Reinstalling/resetting config doesn't help → means it's likely a mod code issue, not just a bad config

it only happens when i try to start a server with a world ok

can you check that ok

[JavidPack]

You'll need to post a client.log, I didn't know this error you are taking about. Also, can you do some testing to determine which other mods need to be enabled to trigger this error? This error should not happen unless another mod is involved.

[Laurenssssssss]

maybe i had spawnsheet activated or i needed to install Heros mod again and reset from the cheathotkeys the Keys and unbind it from CheatHotKeys again that Heros mod has no Interference with CheatHotKeys ok