[Dmitry_DM]

Спасибо большое! Я совсем немного переделал вот так:

Код:

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    OpenDialog1: TOpenDialog;
    Edit1: TEdit;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
   FileName : PWideChar;
implementation

{$R *.dfm}

function CreateProcessWithLogonW(
    lpUsername: LPCWSTR;
    lpDomain: LPCWSTR;
    lpPassword: LPCWSTR;
    dwLogonFlags: DWORD;
    lpApplicationName: LPCWSTR;
    lpCommandLine: LPWSTR;
    dwCreationFlags: DWORD;
    lpEnvironment: Pointer;
    lpCurrentDirectory: LPCWSTR;
    const lpStartupInfo: _STARTUPINFOA;
    var lpProcessInfo: _PROCESS_INFORMATION
  ): Boolean; stdcall; external 'Advapi32.dll';
 
procedure TForm1.Button1Click(Sender: TObject);
var
  startupinfo: _STARTUPINFOA;
  processinformation: _PROCESS_INFORMATION;
begin
  ZeroMemory(@startupinfo, SizeOf(_STARTUPINFOA));
  startupinfo.cb:=SizeOf(_STARTUPINFOA);
  startupinfo.dwFlags:=STARTF_USESHOWWINDOW;
  startupinfo.wShowWindow:=SW_SHOW;
  if OpenDialog1.Execute then
  Edit1.Text:=OpenDialog1.FileName;
  FileName := PWideChar(WideString(Edit1.Text));

  if CreateProcessWithLogonW('Гость', nil, '', 0, nil, FileName, 0, nil, nil, startupinfo, processinformation) then
  begin
    CloseHandle(processinformation.hThread);
    CloseHandle(processinformation.hProcess);
  end else RaiseLastOSError;
end;


end.