Originally Posted By Justin
Notice the error is a write protect error - MESS is not capable of writing to disks inside of zip archives (because it would have to re-zip them every time) so zipped disks behave like write-protected disks. If the emulated computer doesn't like write-protected disks for whatever reason, then you'll just have to use unzipped images. (You might want to keep unmodified backups somewhere though.)

This can be the reason. Thank you for the Info !