The error "Fusion data structures are invalid" indicates a file system issue with the fusion data structure. To fix it, split your Fusion Drive and recreate it. Ensure you back up your Mac before proceeding, as the process below will remove all data on your drives.
Here are the steps:
- Close all apps running on your Mac.
- Open Terminal.
- Run the command below to display information about your Fusion Drive.diskutil cs list
- Look for the Logical Volume Group UUID and the Logical Volume UUID.
- Delete the Logical Volume Group with its UUID. (e.g., diskutil cs delete E03B3F30-6A1B-4DCD-9E14-5E927BC3F5DC)diskutil cs delete LVG_UUID
- Delete the Logical Volume with its UUID.diskutil cs deleteVolume LV_UUID
- Wait for Terminal to complete job.
After your Fusion Drive is split, follow Apple's guide to recreate a Fusion Drive again.