is not a valid winmd file name for this assembly. All types within a Windows Metadata file must exist in a sub namespace ...

'{0}' is not a valid winmd file name for this assembly.  All types within a Windows Metadata file must exist in a sub namespace of the namespace that is implied by the file name.  Types that do not exist in such a sub namespace cannot be located at runtime.  In this assembly, the smallest common namespace that could serve as a filename is '{1}'.