certsrv 40416 Jun 2009
If you get a 404 error in your browser when browsing to the certsrv virtual directory of the CA server (http://<caHostname>/certsrv) more than likely the virtual directory doesn’t exist. To be sure check IIS running on the CA server. From what I’ve read this can happen if Certificate Services are installed before IIS.
To setup the certsrv site run the following in a command prompt on the CA server: