Fixing Smooth Boot Causing Crashes or Freezes During Loading

Confirming Smooth Boot Is the Cause

If your game crashes or hangs while the loading screen is showing, Smooth Boot's threading changes are a likely suspect. To confirm, temporarily move the mod's config file out of the config folder and relaunch. If the game boots normally with default behavior, the config is the problem. If it still crashes, another mod is conflicting and you should check your crash log for the mod named at the top of the stack trace.

Tuning Down Aggressive Settings

Smooth Boot speeds startup by parallelizing work, but some systems or mod combinations cannot handle the extra concurrency. Open the config and lower the thread counts to conservative values, or disable the client-side optimization while leaving server-side enabled (or vice versa) to find which side is unstable.

• Reduce thread counts step by step rather than jumping to the minimum.
• Disable any option that forces a specific loading order, as this can conflict with mods that expect vanilla sequencing.
• If you run a very large modpack, expect to need gentler settings than a lightly modded instance.

Verifying Stability

Relaunch and watch the loading screen for stutters or freezes. Repeat launches a few times, since some crashes are intermittent. Once you find a stable configuration, note the values so you can restore them if a mod update resets your config.