Unhelpful Error Message

Quick Quiz
When an error occurs, you should:
- a) Notify the user what has happened, explain what has been done automatically as a result of the error, and give the user some instruction about what to do (or who to contact) because of the error.
- b) Notify the user with a cryptic, useless, and perhaps scary message.
- c) Do nothing whatsoever and hope nobody notices.
It seems to me that somebody should have caught this during testing. Grumble.
-Devin