Image backup contains all the files on the disk? Or are there exceptions?
To my knowledge, it creates a VHD file, which is a sector-by-sector image of the entire partition. Everything that’s in the partition should be in the image as well.
sector-by-sector image of the entire partition.
This is not entirely true. Microsoft Outlook .ost files aren’t backed up! As at the file backups and as at the image backups.
I want to know maybe there are some another files which are not backed up.
Hmm, that is weird. But I understand the reasoning behind it (you’re fine even if you lose the .ost file because you can just regenerate it).
This is the documentation behind files being excluded from shadow copies https://docs.microsoft.com/en-us/windows/win32/vss/excluding-files-from-shadow-copies