This message means that the CAD sheet indicated contains an IREF that feeds an OREF of the same name. Apparently this is legal, but it certainly is misleading.
--Scanning drawing 1360371C.CAD Circular reference: IREF (PA FN 2 L BRG HIGH TEMP - CH.B).
This error can be built directly into Hyperview. For more information, see the article Building error reports into the M14.