If the VHDX mounts (attaches) but you cannot access the files or the drive appears RAW/corrupted, the issue is likely with the file system (NTFS/ReFS) inside the virtual disk, not the VHDX container itself.
Troubleshooting Virtual Disks: A Guide to Repairing VHDX Files repair vhdx file
Bad sectors, disk I/O errors, or failing RAID controllers on the physical host machine. If the VHDX mounts (attaches) but you cannot
Create a new VHDX of the same size and use a tool like Hyper-V Manager to inspect or "edit" the old disk, attempting to convert it to a new file. This process often forces the system to rebuild the file's index. 5. Preventive Measures disk I/O errors