The properties of the Err object identify an error by number, description,
and source. These properties are set by whatever generated the error. Usually
this is the Visual Basic application or an object used by the Visual Basic application.
They can also be set by a Visual Basic developer in class modules to identify
errors to external users of those class objects (see the section
"Sending Information from a COM Component" in Chapter
12, "Creating a COM Component that Implements Business Rules or Logic").
After an error occurs, the properties of the Err object can be used to identify
the problem and to determine what action, if any, should be taken to correct the
error.
