Sean Wallbridge
First off, hats off to the Petri site for a really good ‘single server/SBS Server’ RPC/HTTPS documentation resource at:
http://www.petri.co.il/configure_rpc_over_https_on_a_single_server.htm
Note that it will work, without the following (back-end selected in the GUI) if the server is single homed, which is most common. However, there is a little bit of extra magic done, when you perform this step, particularly in regards to a multi-homed server (more than one IP address/2 IP Addresses), by reviewing the last step here http://www.petri.co.il/configure_rpc_over_https_on_a_single_server.htm#gc (and in the below screen shot) that is also a DC (such as SBS) – you will get errors/issues about port 6004 and NSPI (when using the tool/website below) or showing the ‘Directory’ as ‘Disconnected’ when using the outlook /rpcdiag tool.
To fix, pay special attention to this section:
http://www.petri.co.il/configure_rpc_over_https_on_a_single_server.htm#gc
Accept the warnings when selecting the option below…
Finally, this utility could prove to be your best friend. They are missing a tonne of error logging detail, in regards to fixing particular issues, however, it should help you narrow in on the issue at hand (in our case, it was complaining that NSPI on TCP 6004 was invalid, though it was properly set).