You can do it like this:
var exeName = Process.GetCurrentProcess().MainModule.FileName;
ProcessStartInfo startInfo = new ProcessStartInfo(exeName);
startInfo.Verb = "runas";
startInfo.Arguments = "restart";
Process.Start(startInfo);
Application.Exit();
The advantage of passing the "restart" parameter is that you can use that as a flag in Program.cs to start another form.