Trouble with the Build

I have previously had no problems with the build and view in browser option until now.
When I try to build and do a "view in browser" it tries to load but has the message "loading" at the top and "waiting for local host" at the bottom.
It does not however manage to load. I am having to view my program in the demo account which works fine.
It also comes up with http://localhost:8086/index.htm?tc=3614734 in the browser address when trying to load.