Why does 7-Zip say VDI files are read-only?

Why can I not edit the VDI file with 7-Zip? I tried running it as administrator and it still didn't work.

When you open a VDI file, 7-Zip first opens the VDI level and then it can open more levels (MBR, NTFS, FAT or ext4). You can see all open levels if you press "Info" button.

7-Zip can't change VDI, MBR, FAT, NTFS, or ISO images. It's a read-only feature. It's difficult to support writing the code to support such complicated formats (it's a wrapper around a wrapper).

More than this... 7-Zip wasn't designed for all of the cool s**t the author added after the fact. It is designed to compress/create/decompress ZIP and 7-Zip files.