KB Issue
When you browse a website running from IIS, you may experience the HTTP/1.1 New Application Failed error.
Issue Details
When changing names in IIS (Internet Information Services), this can sometimes cause issues with the server, making it so it can no longer find the website.
IIS works with the website name, and if the name changes, it can no longer find it, resulting in a 'New Application Failed' error.
Recreate Issue
    Rename the websites within IIS.
  1. Launch [IIS]
  2. Expand [Server-Name (Domain\username)]
  3. Expand [Sites]
  4. Select the website you want to rename, and hit the [F2] key on your keyboard.
  5. Type in a new name for the website, and click the [Enter] key.
Resolve Issue
Taking from the operation above.
  1. Click on [Server-Name (Domain\username)]
  2. Then click on [Restart]
Try loading the website to see if the error is gone and the site loads.