Caused by: java.lang.NoClassDefFoundError: net/minecraftforge/fml/common/registry/RegistryBuilder
at amerifrance.guideapi.api.GuideAPI.(GuideAPI.java:31)
at amerifrance.guideapi.GuideMod.preInit(GuideMod.java:46)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)

On init obviously, guide api 1.10.2-2.0.2-45

Forge version?

2026, MC 1.10.2

That is extremely outdated. Update.