{Q: How do I open a dBASE table without the required MDX file?
  I keep getting an "Index not found..." exception.}
{A: When you create a dBASE table with a production index (MDX), a
  special byte is set in the header of the DBF file. When you
  subsequently attempt to re-open the table, the dBASE driver
  will read that special byte, and if it is set, it will also
  attempt to open the MDX file. When the MDX file cannot be
  opened, an exception is raised.
  To work around this problem, you need to reset the byte (byte
  28 decimal) in the DBF file that causes the MDX dependency
  to zero.
  The following unit is a simple example of how to handle the
  exeption on the table open, reset the byte in the DBF file,
  and re-open the table.}
unit Fixit;
interface
uses
 SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics,
 Controls, Forms, Dialogs, StdCtrls, DB, DBTables, Grids, DBGrids;
type
 TForm1 = class(TForm)
  Table1: TTable;
  Button1: TButton;
  procedure Button1Click(Sender: TObject);
 private
  { Private declarations }
 public
  { Public declarations }
 end;
var
 Form1: TForm1;
implementation
{$R *.DFM}
const
 TheTableDir = 'c:\temp\';
 TheTableName = 'animals.dbf';
procedure RemoveMDXByte(dbFile: string);
 { This procedure accepts a DBF file as a parameter. It will patch}
 { the DBF header, so that it no longer requires the MDX file }
const
 Value: Byte = 0;
var
 F: file of byte;
begin
 AssignFile(F, dbFile);
 Reset(F);
 Seek(F, 28);
 Write(F, Value);
 CloseFile(F);
end;
procedure TForm1.Button1Click(Sender: TObject);
 { This procedure is called in response to a button click. It }
 { attempts to open a table, and, if it can't find the .MDX file, }
 { it patches the DBF file and re-execute the procedure to }
 { re-open the table without the MDX }
begin
 try
  { set the directory for the table }
  Table1.DatabaseName := ThheTableDir;
  { set the table name }
  Table1.TableName := TheTableName;
  { attempt to open the table }
  Table1.Open;
 except
  on E: EDBEngineError do
  { The following message indicates the MDX wasn't found: }
  if Pos('Index does not exist. File', E.Message) > 0 then
  begin
  { Tell user what's going on. }
  MessageDlg('MDX file not found.Attempting to Open
  without Index.', mtWarning, [mbOK], 0);
  { remove the MDX byte from the table header }
  RemoveMDXByte(TheTableDir + TheTableName);
  { Send the button a message to make it think it was }
  { pressed again. Doing so will cause this procedure to }
  { execute again, and the table will be opened without }
  { the MDX }
  PostMessage(Button1.Handle, cn_Command, bn_Clicked, 0);
  end;
 end;
end;
end.