I get this error message: The string was not recognized as a valid DateTime. There is a unknown word starting at index 0.

System.FormatException: The string was not recognized as a valid DateTime. There is a unknown word starting at index 0.

May I know how I can solve the problem? Any assistance will be very much appreciated. Thank you

Below is pat of the code:
OleDbCommand1.Parameters.Add(New System.Data.OleDb.OleDbParameter("PARAM_BOOK_END_DATE", System.Data.OleDb.OleDbType.Date, 16, System.Data.ParameterDirection.Input, False, CType(19, Byte), CType(0, Byte), "", System.Data.DataRowVersion.Current, "2003/04/23"))

OleDbCommand1.Parameters.Add(New System.Data.OleDb.OleDbParameter("PARAM_BOOK_START_TIME", System.Data.OleDb.OleDbType.VarChar, 4000, System.Data.ParameterDirection.Input, False, CType(0, Byte), CType(0, Byte), "", System.Data.DataRowVersion.Current, "1000"))