This should be easy to understand

No, I couldn't have entered data into a database if I was not given said data to begin with.

Error Messages

To follow Microsoft's lead, when writing code, the more complicated or difficult the error is to diagnose, make sure that you make the error messages more vague and nondescript, respectively. For instance, if your user has no way of knowing what the cause of the problem is, make sure to make the error message state something along the lines of "Error 10: Unknown error" or "Error 2: General Error", that way the user has absolutely no way of easily diagnosing what the problem is. Or, and this is my favorite, when they go to Online Help, the returned result for the error message is "You should not receive this error".