Steps I took...
I have a folder called WAB/Current
I copied all of the WAB 1.0 files into this folder.
I opened my browser (which DIDN'T open on it's own) and navigated to the URL for WAB.
I went back to the WAB/Current folder and copied all of the WAB 1.1 files this time.
Double-clicked startup.bat and got this error message.