public ActionResult Delete(UserTaskViewModel model)
        {
            var userTask = userTaskRepository.GetById(model.Id);

            if (userTask == null)
            {
                throw new ArgumentException(string.Format("User task with Id [{0}] does not exist", model.Id));
            }

            try
            {
                userTaskRepository.DeleteAndSubmit(userTask);

                base.SetSuccessMessage("The user task has been deleted.");
                return(RedirectToAction("Index"));
            }
            catch (Exception ex)
            {
                base.SetErrorMessage("Whoops! Couldn't delete the task. The error was [{0}]", ex.Message);
            }

            return(View(model));
        }