>>What do you have there?
>
>Maybe I'm barking up the wrong tree but isn't that your own code (in 'SysManager.Web.Areas.AccountingAudit.Controllers.PaymentTypesController)

Good point. I checked the code for this controller and it has

        [Route("")]
        public ActionResult Index()
        {
            return View(new PaymentTypeSearchViewModel());
        }

In similar controllers we just have return View();

I'll try to comment new here and see if it gets me farther.

UPDATE. No, this didn't help - same error.