If, for reasons unknown to me you stumble upon problems installing Remote Desktop Web Access on Windows Server 2012 in the shape of Error 0x800f0922, the following solution might just be your knight in shining armor. Firstly, locate any certificate bound to a site that doesn't show up in IIS with the following command...
netsh http show sslcert
If anything shows up, delete it with the following command for IPv4...
netsh http delete sslcert ipport=0.0.0.0:443
And for IPv6, the following...
netsh http delete sslcert ipport=[::]:443
That's it for now. Your Remote Desktop Web Access role should now install just fine.
