Welcome to the Community,
please check whether all files that make up the virtual disk are present in the VM's folder/bundle.
With default settings, each virtual disk (and/or snapshot) consists of a descriptor file (e.g. "Windows 10 x64.vmdk"), and several data files (e.g. "Windows 10 x64-s00x.vmdk"). The descriptor file contains the list of the required data files.
André
