[marcoszorrilla]

A ver si esto lo que pides:

Código Delphi [-]
unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
begin
ShellExecute(0, 'open', 'mailtoepeperez @asucorreo.com', nil, nil,0);
end;

end.

Un Saludo.