LIBRARY access;

USES
  SysUtils,
  ADODB, DB,
  Classes;

{$R *.res}

   FUNCTION Search(Temp: TComponent): TDataSourcet;
   VAR
      ADOQ_SQL: TADOQuery;
      DS_SQL  : TDataSource;
      Path : String;
   BEGIN
      GetDir( 0 , Path);

      ADOQ_SQL := TADOQuery.Create(Temp);
      DS_SQL   := TDataSource.Create(Temp);

      WITH ADOQ_SQL DO
      BEGIN
         ConnectionString := 'Provider=MSDASQL.1;Persist Security Info=False;User ID=admin;Data Source=MS Access Database;Mode=ReadWrite;Initial Catalog=' + Path + '\DB\access.mdb';
      END;

      WITH ADOQ_SQL.SQL DO
      BEGIN
         Clear;
         Add('SELECT * FROM Privilege');
      END;
      ADOQ_SQL.Open;
      DS_SQL.DataSet := ADOQ_SQL;

      result := DS_SQL;
   END;

EXPORTS Search;
BEGIN

END.

   PROCEDURE TForm1.Button1Click(Sender: TObject);
   VAR
      Handle : integer;
      Search :  function (Temp: TComponent) : TDataSource;
   BEGIN

     Handle := LoadLibrary(PChar('access.dll'));
     IF Handle <>  0  THEN
     BEGIN
        @Search := GetProcAddress(PlgHandle, 'Search');
        IF @Search <> nil then
        BEGIN
           DBLookupComboBox1.ListSource := search(self);
           DBLookupComboBox1.ListField := 'name';
           DBLookupComboBox1.KeyField := 'id';
        END ELSE
           ShowMessage('Внимание! Ошибка! Данная библиотека (dll) ''Битая''!');
        FreeLibrary(PlgHandle);
      END ELSE
         ShowMessage('Внимание! Ошибка! Dll не найдена!');
   END;

Project Project.exe raised exception class EInvalidPointer with message 'Invalid pointer operation'. Process stopped....

   FUNCTION SH(Temp: TComponent; var Auto: TDataSource): Integer; far;
   VAR
   ...

   ...
      ADOQ_SQL.Open;
      DS_SQL.DataSet := ADOQ_SQL;
      Auto := DS_SQL;

      Result :=  0 ;
   END;

   PROCEDURE TForm1.Button1Click(Sender: TObject);
   VAR
      Handle : integer;
      Sh :  FUNCTION (Temp: TComponent; VAR Auto:TDataSource) : Integer;
      Auto:TDataSource;
   BEGIN
     Handle := LoadLibrary(PChar('access.dll'));
     IF Handle <>  0  THEN
     BEGIN
        @Sh := GetProcAddress(Handle, 'SH');
        IF @SH <> nil THEN
        BEGIN
           IF sh(self, Autott) =  0  THEN BEGIN
              DBLookupComboBox1.ListSource := Autott;
              DBLookupComboBox1.ListField := 'name';
              DBLookupComboBox1.KeyField := 'id';
              DBGrid1.DataSource := Autott;
           END;
        END ELSE
           ShowMessage('Внимание! Ошибка! Данная библиотека (dll) ''Битая''!');
        FreeLibrary(Handle);
     END ELSE
        ShowMessage('Внимание! Ошибка! Dll не найдена!');
   END;

              DBGrid1.DataSource := Autott;