I recently followed the instructions to set up octopus and when I visited the site on localhost I received a 403.14 error since IIS didn’t seem to understand how to run an MVC website and was trying to perform a directory listing of the site root.
I found that I needed to enable HTTP redirection to get the site to work. I did this by performing the following steps:
Server Manager -> Roles -> Web Server -> Roles Services -> HTTP Redirection.
I found the answer in a stack overflow post about problems with MVC3 and IIS7: http://stackoverflow.com/questions/5059897/problem-running-mvc3-app-in-iis-7
This might be a useful addition to the getting started page: http://help.octopusdeploy.com/kb/getting-started/installing-octopus-and-tentacles