HTTP could not register URL [url]. Your process does not have access rights to this namespace

I was trying to build a project that I inherited (ASP C# ~.Net4) and I got the following error

Please try changing the HTTP port to 8732 or running as Administrator.
System.ServiceModel.AddressAccessDeniedException: HTTP could not register [url]. Your process does not have access rights to this namespace (see http://go.microsoft.com/fwlink/?LinkId=70353 for details). —> System.Net.HttpListenerException: Access is denied

…

System.Net.HttpListenerException (0x80004005): Access is denied
at System.Net.HttpListener.AddAllPrefixes()
at System.Net.HttpListener.Start()
at System.ServiceModel.Channels.SharedHttpTransportManager.OnOpen()

All the issue was is that Visual Studio could not access certain files since it does not have administrator access. Run as administrator, and you should no longer have a problem. Also go to properties (Of Visual Studio) and select the run as administrator for future reference so you don’t run into the issue again.

• To run as an administrator, right click Visual Studio and select Run as Administrator from the context menu.
• To run as administrator all the time, right click Visual Studio, then go to properties in the context menu
  • Got to the compatibility tab, then select Run this program as an administrator.