UnknownMemberName Element (ASSL)
Contains the caption, in the default language of the dimension, for the unknown member of the dimension.
The value of the UnknownMemberName element supplies the caption used for the unknown member. The member ID of the unknown member is Dimension.UnknownMember, where Dimension is the unique name of the dimension, and cannot be changed.
The element that corresponds to the parent of UnknownMemberName in the Analysis Management Objects (AMO) object model is Dimension.