As I ran the site within IIS to demo across the network, I think I gave IIS_IUSRS access to the presentation folder or a sub folder within that - can't remember exactly.
its sending me on nopCommerce 4.00 - Source code (28 MB) download which require VS 2017 or .net Core . I want nopcommerce in MVC 4 with VS2010. also https://github.com/nopSolutions/nopCommerce is uncompatible for 2010