Can't read linked file error message

I keep seeing the “can’t read linked file” message in the block manager. (see attached) When I hit the update button the file seems to update but not all of the changes show up and some of them do. Any thoughts? I’m inserting an AutoCAD 2010 dwg file that has xrefs in it if that helps.

Dennis

An update: If I exit Rhino and restart the program and re-open the drawing all is up-to-date.