Troubleshooting

Most problems are one of the four below.

A mod does nothing at all

Work through this list top to bottom:

1. Is Mycel installed? Every MyCelium mod needs the Mycel jar in the same mods folder. Without it the game usually refuses to start, but double-check all jars are there and for the right loader.
2. Is the mod enabled? Check its config file (config/instantxp.json or config/autoblockrefiller.json) and make sure enabled is true.
3. Are the conditions right? InstantXP only collects orbs inside its radius and never for spectators. AutoBlockRefiller only refills blocks into slots that are actually empty, from the main inventory (or hotbar with searchHotbar). Check the mod's features page if the behavior surprises you.
4. Is another mod interfering? Try with only Mycel and the one mod installed to confirm.

Game crashes on startup

1. Check the versions. MyCelium mods need Minecraft 26.3, Java 25, Mycel 1.1.0, and the matching loader generation (Forge 66+, NeoForge 26.3.0.1-beta+, Fabric Loader 0.19.5+ with Fabric API). A wrong Minecraft or Java version is the most common cause.
2. Check the loader. A Fabric jar on Forge (or any mix-up) will not load. The file names tell you which is which.
3. Read the crash report. It names the failing mod near the top. If it points at a MyCelium mod or Mycel, include it when asking for help.

Config changes do nothing

Editing a config file while the game runs does nothing until you reload it (/mycel reload instantxp or /mycel reload autoblockrefiller) or restart. Also check you edited the right file: singleplayer and each server have their own config folder. A mangled file falls back to defaults with a warning in the log; delete it and restart for a fresh one.

Still stuck?

Gather these three things and open an issue on the mod's GitHub page (InstantXP, AutoBlockRefiller):

1. The output of /mycel info (versions and platform).
2. Your mod's config file.
3. The log or crash report from logs/latest.log.