Home » Cannot create/shadow copy ‘DotNetOpenAuth.OAuth’ when that file already exists. – ASP.NET MVC4 ASP.NETCannot create/shadow copy ‘DotNetOpenAuth.OAuth’ when that file already exists. – ASP.NET MVC4 January 16, 2014 by Sunny Sharma Sunny Sharma·January 16, 2014·1 min read Error: Cannot create/shadow copy ‘DotNetOpenAuth.OAuth’ when that file already exists. How I solved it: Try to re-build the solution and it should work. It worked in my case, I’m not kidding ! Sunny SharmaSecurity and engineering leader. Notes from running AI, Azure and security in production.All posts