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I have a problem opening an Access DB in an OLE server created with
Delphi 3.
I have prepared a very short example that demonstrate how the server
work (and crash):

- the client ask the server to open the DB
- the server open the db
- the server close the db
- the user close the client
- the user get "Access violation ...." :-(

I have tried not to use a db in the server, and everything seem to go
right; I have tried to use a Paradox DB, and everything seem to go
right; the problem seems to happen only when I open an Access 95/97 db
in the OLE server; I'm using Delphi 3.02, BDE 4.50, DAO 3.5.
Is someone able to give me a possible solution for this problem?
Does the problem regard DAO, OLE, BDE, Delphi or my inexperience with OLE?

this is the source code of the minimal example:

**** This is the server code:

library DBServer;

uses
  ComServ,
  DBServer_TLB in 'DBServer_TLB.pas',
  Unit1 in 'Unit1.pas' {DBAServer: CoClass};

exports
  DllGetClassObject,
  DllCanUnloadNow,
  DllRegisterServer,
  DllUnregisterServer;

{$R *.TLB}

{$R *.RES}

begin
end.

--------------------------------------------------------------------

unit Unit1;

interface

uses
  Forms, DBTables, Dialogs, ComObj, ActiveX, DBServer_TLB;

type
  TDBAServer = class(TAutoObject, IDBAServer)
  protected
        procedure Apri; safecall;
  end;

implementation

uses ComServ;

procedure TDBAServer.Apri;
var DatLocale: TDatabase;
begin
        showmessage('OLE Server');
        DatLocale:= TDatabase.Create(Application);
        DatLocale.AliasName:= '';
        DatLocale.DatabaseName:= 'MyDatabase1';
        DatLocale.DriverName:= 'MSACCESS';
        //DatLocale.DriverName:= 'STANDARD';
        DatLocale.LoginPrompt:= False;
        DatLocale.Params.Values['DATABASE NAME']:=
'h:\Documenti\db1.mdb';
        //DatLocale.Params.Values['DATABASE NAME']:=
'H:\Progetti\Prg_delphi3\ProvaOLE\Server\db\tAnagrafica.db';
        DatLocale.Params.Values['USER NAME']:= '';
        DatLocale.Params.Values['OPEN MODE']:= 'READ/WRITE';
        DatLocale.Params.Values['LANGDRIVER']:= '';
        DatLocale.Params.Values['SYSTEM DATABASE']:= '';
        DatLocale.Params.Values['PASSWORD']:= '';
        DatLocale.SessionName:= 'Default';
        DatLocale.open;
        showmessage('connected = true');
        DatLocale.close;
        DatLocale.free;
        showmessage('connected = false');
end;

initialization
  TAutoObjectFactory.Create(ComServer, TDBAServer, Class_DBAServer,
ciMultiInstance);
end.

--------------------------------------------------------------------

unit DBServer_TLB;

{ This file contains pascal declarations imported from a type library.
  This file will be written during each import or refresh of the type
  library editor.  Changes to this file will be discarded during the
  refresh process. }

{ DBServer Library }
{ Version 1.0 }

interface

uses Windows, ActiveX, Classes, Graphics, OleCtrls, StdVCL;

const
  LIBID_DBServer: TGUID = '{4FD075B0-E00F-11D1-91DE-0020A9004BBC}';

const

{ Component class GUIDs }
  Class_DBAServer: TGUID = '{4FD075B2-E00F-11D1-91DE-0020A9004BBC}';

type

{ Forward declarations: Interfaces }
  IDBAServer = interface;
  IDBAServerDisp = dispinterface;

{ Forward declarations: CoClasses }
  DBAServer = IDBAServer;

{ Dispatch interface for DBAServer Object }

  IDBAServer = interface(IDispatch)
    ['{4FD075B1-E00F-11D1-91DE-0020A9004BBC}']
    procedure Apri; safecall;
  end;

{ DispInterface declaration for Dual Interface IDBAServer }

  IDBAServerDisp = dispinterface
    ['{4FD075B1-E00F-11D1-91DE-0020A9004BBC}']
    procedure Apri; dispid 1;
  end;

{ DBAServerObject }

  CoDBAServer = class
    class function Create: IDBAServer;
    class function CreateRemote(const MachineName: string):
IDBAServer;
  end;



implementation

uses ComObj;

class function CoDBAServer.Create: IDBAServer;
begin
  Result := CreateComObject(Class_DBAServer) as IDBAServer;
end;

class function CoDBAServer.CreateRemote(const MachineName: string):
IDBAServer;
begin
  Result := CreateRemoteComObject(MachineName, Class_DBAServer) as
IDBAServer;
end;


end.

--------------------------------------------------------------------

**** This is the client code:

program DBClient;

uses
  Forms,
  Unit1 in 'Unit1.pas' {Form1},
  DBServer_TLB in 'C:\Program Files\Borland\Delphi
3\Imports\DBServer_TLB.pas';

{$R *.RES}

begin
  Application.Initialize;
  Application.CreateForm(TForm1, Form1);
  Application.Run;
end.

--------------------------------------------------------------------

unit Unit1;

interface

uses
  DBServer_TLB,  Windows, Messages, SysUtils, Classes, Graphics,
Controls, Forms, Dialogs,
  StdCtrls;

type
  TForm1 = class(TForm)
        cmdApri: TButton;
        procedure cmdApriClick(Sender: TObject);
  private
        { Private declarations }
  public
        { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.cmdApriClick(Sender: TObject);
var Mydb: IDBAServer;
begin
        Mydb:= CoDBAServer.Create;
        Mydb.Apri;
end;

end.


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