"main may not be within the org.bukkit namespace"

Server log

org.bukkit.plugin.InvalidDescriptionException: main may not be within the org.bukkit namespace

What it means

Your main class sits in a package that starts with org.bukkit, which belongs to the server API. The server refuses the plugin.

What causes it

The main value starts with org.bukkit., usually because the class was created inside the wrong package.

How to fix it

Before

main: org.bukkit.myplugin.MyPlugin

After

main: com.yourname.myplugin.MyPlugin

Move the class to your own package and update main to match. Use a domain you own or your name, so it does not clash with other plugins.

Check the whole file. Paste your plugin.yml or drop the plugin jar into Permistry. It finds this and about 40 other problems, and explains each one in plain words. It runs in your browser and nothing is uploaded.

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