The BEXPORT_PARMS structure that is used as a parameter for the BatchExport function must be initialized to zero before use. You can do this by calling the Win32 ZeroMemory function. By zeroing this structure, you ensure that default processing is invoked for fields that are not filled in. For example, pointers to callback functions need to be nonzero if a callback is to be used. However, BatchExport interprets a zero pointer for an export callback function as a request for it to write to a file. If all the callback functions are zeroed and no export file is specified, the function call returns an error.