http://blogs.msdn.com/kcwalina/archive/2005/03/16/396787.aspx
Should Exceptions Carry Error Code Information
http://blogs.msdn.com/kcwalina/archive/2005/05/27/422681.aspx
Error Raising and Handling Guidelines
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpgenref/html/cpconerrorraisinghandlingguidelines.asp
Error Code Paradigms
http://blogs.msdn.com/larryosterman/archive/2005/06/02/424398.aspx
Наибольшего осмысления требует вот это: Do not use error codes because of concerns that exceptions might affect performance negatively.