Figure: Log every error
Not to say though that there is any ideal error message - a great error is one that has been eliminated! In packaged products, every unhandled error is our problem.
In the old days, unhandled errors would be stored in a local Access db, but now all unhandled errors should be automatically emailed to the product team. This is a proactive and polite approach to dealing with unhandled errors. If it's serious we will contact the client to resolve the situation - they get a bit of a surprise and think we have ESP!
Remember what it is like to have good service in a restaurant. A good waiter knows when to interrupt you, when to leave you alone and how to do it all in a courteous and respectful way.