This error message occurs within Forge servers when you add, remove or modify a mod, while attempting to use your same existing world.
To bypass this, visit the "Console" on your VillagerHost control panel, andthen type: `/fml confirm` into the console.
Please note we reccomend creating a backup of your world before doing so, or generating a brand new world to be on the safe side.
Please wait a few seconds, and your server will startup as normal.
Still Stuck? Please open a Support ticket and our team will be happy to help you!