hello amos, thanks for the quick reply. i've changed the config according the your link ref. owa. but i still have doubts because it is still not working. i didn't quite understand what you mean when you said: "All requests entering through this port are re-written with the domain name "mail.my-domain.com". Update your EXCH ACL to permit "mail.my-domain.com" and ensure that the exchange server believes its public domain name is "mail.my-domain.com"." my public domain name which is "mail.my-domain.com" is never known by the exchange server. the only name it knows is "exchange-server.local", which is reflected in the self-signed certificate contained in the cache_peer clause. the public certificate (and its related public domain "mail.my-domain.com" or "mail.my-domain.com/owa", is only known by the squid server. because of a couple of reasons i am not able to install the public geotrust certificate into my exchange server. and if i could, there would be no need to use squid in between, once exchange could handle the outside connections by itself. i am just adding squid to this scenario because squid needs to handle the public internet connections (based on the public geotrust certificate), and pass it on to exchange as an internal client would do (based on self-signed certificate). so, my actual config is now like this: ############## https_port squid-ip-address:443 cert=/etc/squid3/public_geotrust_cert.pem defaultsite=mail.my-domain.com connection-auth=off cache_peer exchange-ip-address parent 443 0 no-query originserver login=PASS ssl sslcert=/etc/squid3/self_signed_cert.pem name=owaServer acl OWA dstdomain exchange-server-name.local cache_peer_access owaServer allow OWA never_direct allow OWA http_access allow OWA http_access deny all miss_access allow OWA miss_access deny all ############## and i still got the error in cache.log: TCP_DENIED/403 4027 GET http://mail.my-domain.com/owa - NONE/- text/html but, if I change: acl OWA dstdomain exchange-server-name.local to acl OWA dstdomain mail.my-domain.com then i got several of these in cache.log: TCP connection to exchange-ip-address/443 failed fwdNegotiateSSL: Error negotiating SSL connection on FD 14: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed (1/-1/0) temporary disabling (Service Unavailable) digest from 'exchange-ip-adress' and this on the browser: failed to establish a secure connection with owaServer / returned: (71) Protocol error thanks again, sidnei -----Mensagem original----- De: Amos Jeffries [mailto:squid3@xxxxxxxxxxxxx] Enviada em: quinta-feira, 8 de setembro de 2011 21:08 Para: squid-users@xxxxxxxxxxxxxxx Assunto: Re: reverse proxy shows error 403 denied On 09/09/11 02:29, Sidnei Moreira wrote: > hello, > > i have configured squid to reverse-proxy an internet connection going > into my internal exchange server. > the squid configuration section is like this one: > > ############################## > # ip 10.0.1.1 - squid server > # ip 10.0.1.2 - ms-exchange server > https_port 10.0.1.1:443 cert=/etc/squid3/geotrust_cert.pem > defaultsite=mail.my-domain.com All requests entering through this port are re-written with the domain name "mail.my-domain.com". Update your EXCH ACL to permit "mail.my-domain.com" and ensure that the exchange server believes its public domain name is "mail.my-domain.com". > cache_peer 10.0.1.2 parent 443 0 no-query originserver login=PASS ssl > sslcert=/etc/squid3/selfsigned.pem name=exchangeServer > > acl EXCH dstdomain .rpc_domain_name > cache_peer_access exchangeServer allow EXCH cache_peer_access > exchangeServer deny all > > never_direct allow EXCH > http_access allow EXCH > http_access deny all > miss_access allow EXCH > miss_access deny all > ############################## > > but, when i try to connect from the internet i receive a denying page, > and the cache log says: > TCP_DENIED/403 3861 GET https://mail.my-domain.com/owa - NONE/- > text/html > That looks like an OWA request. They require some different peer configuration than RPC. http://wiki.squid-cache.org/ConfigExamples/Reverse/OutlookWebAccess IIRC it had something to do with OWA doing client certificate verification. Amos -- Please be using Current Stable Squid 2.7.STABLE9 or 3.1.15 Beta testers wanted for 3.2.0.11