Thanks for the response - just to be clear I have got outlook web access (OWA) working fine with nginx except for the 'Outlook Anywhere' functionality (was called RPC over HTTP(s)).

I think this is all related to the fact that the methods used (RPC_IN_DATA and RPC_OUT_DATA) create an artificially large content-length (1GB on the RPC_IN_DATA) to keep the connection open. Because nginx proxy tries to pre-fetch this (which will not complete) the end users' connection just times out. I have tried turning various buffering switches off but it still is not working. There is a really good explanation of the problem I have on an apache bug which has been re-opened (see http://209.85.229.132/search?q=cache:ejPagX7DOF8J:issues.apache.org/bugzilla/show_bug.cgi%3Fid%3D40029+rpc_in_data+%221073741824+bytes%22&hl=en&gl=uk&strip=1) so nginx is not alone.

I don;t understand if this is something that will never work in nginx/reverse proxies or if it is just down to configuration. I would be really interested to know if anyone has got RPC over HTTPS working through nginx. My debug log just shows the connection timing out while it is waiting for 1GB of data that it wont get!

cates.