A user has an issue associated with Drawing and Sheet models losing association with the master model (created using the Create Drawing tool). Once the links are broken they are no longer able to re-establish the control (Global Display) linkage between the master model and the Drawing/sheet models despite using the key in command “Reference Synchronize Levels All”.
Open the Reference Presentation dialog box inside the drawing model. Next to "Synchronize View", click the first icon, "Update From Saved View". This will update the reference´s view attributes to match the source saved view´s view attributes.
http://communities.bentley.com/products/microstation/f/273/p/91402/262048#262048