Common errors

The server does not start

Check, in this order:

1. the JAR matches the modloader and Minecraft version;
2. Java matches the supported line;
3. Forge/NeoForge and dependencies use compatible versions;
4. there are no duplicate copies of the mod in mods;
5. the latest.log and crash report show the first relevant exception.

A non-operator player cannot use a kit

Run:

/msb permission status

Then verify:

• active backend;
• complete kit node;
• specific grant or deny and the parent permission;
• availability of FTB Ranks or another external handler;
• operatorBypass should not replace proper permissions for regular players.

I selected built-in, but FTB Ranks still appears

Run:

/msb permission backend built_in
/msb permission status

The first command saves the loader configuration value. If you edited the TOML manually, restart the server or follow the Forge/NeoForge configuration reload lifecycle.

Corrupted JSON

Stop the server and look for a .corrupt-<timestamp>.bak backup. Do not replace the document with {} without understanding its schema. Attach sanitized copies to your bug report when analysis is needed.

MineSkin fails

• confirm that the token exists and has no extra whitespace;
• test a publicly reachable HTTPS URL;
• review MineSkin service availability and quotas;
• never publish the token when requesting support.

The skin does not appear immediately

The texture property is propagated to connected players, but the client may retain visual state. Reconnect once before opening a bug.