Hello, I’m coming back to you, just to tell you I’ve found a squid alternative for a linux frontend server, in front of exchange 2007 or 2010 CAS server. It works with owa, activesync and outlook anywhere in ntlm, and it’s free. I was never able to make squid working for that configuration, in fact all was working except RPC over https, or outlook anywhere in NTLM auth, so I gave up with squid. Recently I check if someone found a solution, and I found this page : http://www.stevieg.org/e2010haproxy/ I try it, and that works like a charm, I don’t know exactly how it works, it’s load balancing mode, you even not need to install certificates of exchange server, it relays all request directly to exchange. And I exactly wanted this ! [INTERNET] ←→ [HAPROXY PRE-CONFIGURED VM - IN DMZ] ←→ [EXCHANGE SERVER - IN LAN] Hope that can help. I’ll get out of this mailing list now, squid is a very good program, thanks for all you did and help for my researches. Kind regards Clem