Mods are extremely popular in Satisfactory and it is considered one of the best games to have mods in due to its open-ended nature. Unfortunately, using mods can also introduce new errors. The "Plugin SML Failed" error in Satisfactory usually indicates an issue with a specific plugin that is breaking the core functionality of the game. If you encounter this issue, here is what you should do next.
How to fix the error Satisfactory Plugin SML failed to load
This isn’t the first time this error has appeared, and every time it does, players try to uninstall the game’s mod manager, but are unsuccessful. What will most likely fix the Plugin SML Failed error is completely deleting your mods folder. Go to this path: C:/SteamLibrary/steamapps/common/Satisfactory/FactoryGame/Mods and delete the folder.
After most updates (especially one as big as Update 1.0 which takes the game from 5+ years of Early Access to a full release), mods are found to be broken. It is up to the original modders to update the mod to be compatible with the latest update and you can follow their social media channels to stay up to date. Until then, removing the mods is the only solution to avoid the plugin bug which can cause crashes.
To temporarily disable mods without deleting the mods folder, open Satisfactory Mod Manager and disable the 'Mods' button. If this doesn't work, navigate to %appdata%/SatisfactoryModManager/profiles, delete the vanilla folder, restart SMM, and disable 'Mods' again.