ADO Error Codes
In addition to the provider errors returned in the Error objects of the Errors collection, ADO itself can return errors to the exception-handling mechanism of your run-time environment. Use the error trapping mechanism your programming language, such as the On Error statement in Microsoft® Visual Basic or the try-catch block in Microsoft Visual C++® or Microsoft Visual J++® to capture ADO errors.
For the list of ADO error codes, see ErrorValueEnum.