Foros Club Delphi - Falla al enviar mail en algunas PCs

Hola Foro

tengo la rutina para enviar mails que la consegui de un compañero del club delphi, esta rutina la uso hace un par de años y pude comprobar que en algunas PCs anda y en otras me da error que no puede enviar el mail.

He revisado el puerto que sea el 25 y otras cositas, pero no pude detectar cual es el problema.

Les dejo la rutina y si alguno me puede dar una idea se lo agradezco.

saludos tulio

dirmail:='mail@hotmail.com ';
mail := TStringList.Create;
try
mail.values['to'] :=dirmail;
mail.values['subject'] := 'Leyenda';
mail.values['attachment0'] :='';
// mail.values['attachment1']:='C:\Test2.txt';
sendEMail(Application.Handle, mail);
Finally
mail.Free;
End;

Function tF_Mails.SendEMail(Handle: THandle; Mail: TStrings): Cardinal;
type
TAttachAccessArray = array [0..0] of TMapiFileDesc;
PAttachAccessArray = ^TAttachAccessArray;
var
MapiMessage: TMapiMessage;
Receip: TMapiRecipDesc;
Attachments: PAttachAccessArray;
AttachCount: Integer;
i1: integer;
FileName: string;
dwRet: Cardinal;
MAPI_Session: Cardinal;
WndList: Pointer;
begin
dwRet := MapiLogon(Handle,
PChar(''),
PChar(''),
MAPI_LOGON_UI or MAPI_NEW_SESSION,
0, @MAPI_Session);

if (dwRet <> SUCCESS_SUCCESS) then
begin
MessageBox(Handle,
PChar('Error while trying to send email'),
PChar('Error'),
MB_ICONERROR or MB_OK);
end
else
begin
FillChar(MapiMessage, SizeOf(MapiMessage), #0);
Attachments := nil;
FillChar(Receip, SizeOf(Receip), #0);

if Mail.Values['to'] <> '' then
begin
Receip.ulReserved := 0;
Receip.ulRecipClass := MAPI_TO;
Receip.lpszName := StrNew(PChar(Mail.Values['to']));
Receip.lpszAddress := StrNew(PChar('SMTP:' + Mail.Values['to']));
Receip.ulEIDSize := 0;
MapiMessage.nRecipCount := 1;
MapiMessage.lpRecips := @Receip;
end;

AttachCount := 0;

for i1 := 0 to MaxInt do
begin
if Mail.Values['attachment' + IntToStr(i1)] = '' then
break;
Inc(AttachCount);
end;

if AttachCount > 0 then
begin
GetMem(Attachments, SizeOf(TMapiFileDesc) * AttachCount);

for i1 := 0 to AttachCount - 1 do
begin
FileName := Mail.Values['attachment' + IntToStr(i1)];
Attachments[i1].ulReserved := 0;
Attachments[i1].flFlags := 0;
Attachments[i1].nPosition := ULONG($FFFFFFFF);
Attachments[i1].lpszPathName := StrNew(PChar(FileName));
Attachments[i1].lpszFileName :=
StrNew(PChar(ExtractFileName(FileName)));
Attachments[i1].lpFileType := nil;
end;
MapiMessage.nFileCount := AttachCount;
MapiMessage.lpFiles := @Attachments^;
end;

if Mail.Values['subject'] <> '' then
MapiMessage.lpszSubject := StrNew(PChar(Mail.Values['subject']));
if Mail.Values['body'] <> '' then
MapiMessage.lpszNoteText := StrNew(PChar(Mail.Values['body']));

WndList := DisableTaskWindows(0);
try
Result := MapiSendMail(MAPI_Session, Handle,
MapiMessage, MAPI_DIALOG, 0);
finally
EnableTaskWindows( WndList );
end;

for i1 := 0 to AttachCount - 1 do
begin
StrDispose(Attachments[i1].lpszPathName);
StrDispose(Attachments[i1].lpszFileName);
end;

if Assigned(MapiMessage.lpszSubject) then
StrDispose(MapiMessage.lpszSubject);
if Assigned(MapiMessage.lpszNoteText) then
StrDispose(MapiMessage.lpszNoteText);
if Assigned(Receip.lpszAddress) then
StrDispose(Receip.lpszAddress);
if Assigned(Receip.lpszName) then
StrDispose(Receip.lpszName);
MapiLogOff(MAPI_Session, Handle, 0, 0);
end;
end;