Outlook MAPI behind Squid to use RPC over HTTP function

["michael.jf.jiang@xxxxxxxxx" <michael.jf.jiang@xxxxxxxxx>]

Dear All,

I got some trouble about Outlook MAPI to use RPC over HTTP function
which is behind a squid proxy, it seems the authentication is always
failed. my situation is,
Outlook --> Squid Proxy --> Front-end Exchange server(IIS)-->Backend 
Exchange
server

Any help will be highly appreciated.

Michael Jiang