CDaoException::m_nAfxDaoError

Remarks

Contains an MFC extended error code. This code is supplied in cases where a specific component of the MFC DAO classes has erred.

Possible values are:

NO_AFX_DAO_ERROR The most recent operation did not result in an MFC extended error. However, the operation could have produced other errors from DAO or OLE, so you should check m_pErrorInfo and possibly m_scode.
AFX_DAO_ERROR_ENGINE_INITIALIZATION MFC could not initialize the Microsoft Jet database engine. OLE might have failed to initialize, or it might have been impossible to create an instance of the DAO database engine object. These problems usually suggest a bad installation of either DAO or OLE.
AFX_DAO_ERROR_DFX_BIND An address used in a DAO record field exchange (DFX) function call does not exist or is invalid (the address was not used to bind data). You might have passed a bad address in a DFX call, or the address might have become invalid between DFX operations.
AFX_DAO_ERROR_OBJECT_NOT_OPEN You attempted to open a recordset based on a querydef or a tabledef object that was not in an open state.

For more information about DFX, see the article DAO Record Field Exchange (DFX) in Visual C++ Programmer's Guide.