If you experience an issue and it’s not listed here, please open a new issue and a contributor will help you further.
Could not find tools.jar
If you encounter this error when building, you most likely don’t have the Java Development Kit (JDK) installed. Head over to here to download the oracle JDK. Install it and try again.
Minecraft not loading at all
Note: only applicable if running through Forge and not an IDE.
.jar are you using in your
mods folder? Make sure to use the one that ends with
Just doesn’t work when using runClient
Don’t use that, try running it through your IDE or building and running forge normally
Crashes before game starts with SpongePowered error
Make sure your workspace is clean and run ./gradlew clean ./gradlew setupDecompWorkspace ./gradlew build
Crashes before game starts with some obscure Java error
Set your application configuration’s JRE in Intellij to a manual path to a downloaded and extracted Oracle Java 8 JRE
Please make sure you’re on the latest version of forge before proceeding!
Look for where it crashed and go to the line it crashed at. Make sure you’re not referencing
mc.world when either of those are null, ie have a
if (mc.player == null) return; before you reference those.
When using Intellij / Eclipse
Crashes in game but it worked fine / errors link to files you haven’t changed