CheckerMark79

Alright, thanks to someone from the Forge Discord I managed to solve the issue. If anyone ever gets this error: java.lang.RuntimeException: java.lang.StringIndexOutOfBounds: begin 0, end -1, length 3 Delete the client-extra.jar, found under external libraries, and refresh your gradle. Also make sure you are using Java 16 (As of 1.17+) This solved the issue for me, which took me days.

After having a conversation with SizableShrimp in the Forge Discord I wanted to aks for help on the forums. My mod works completely fine, it compiles fine, genIntellijRuns works fine, but every time I try to use :runClient I experience this error: https://pastebin.com/ekaF1MBL What I have been told is that it is trying to load the eez class from the client-extra.jar. Someone else with a similiar issue deleted all the classes in this .jar and which fixed the issue, but I'm still getting the same error after deleting those classes. I already did things like invalidate caches, and tried to add this to runs in the build.gradle: property 'legacyClassPath', '{minecraft_classpath}' but nothing works. I also tried to run the latest MDK without changing any code but got the same error. Does anyone else have an idea what I need to do? Or is this an issue on Forge's side that I need to report on GitHub?