Hi,When we build the Front End server to provide access of servies like HTTP, IMAP,POP etc then do we require to have HTTP website running on the backend? Regards, Pushkal MishrA

What version of Exchange? Regardless, all versions of Exchange require IIS in some form on a mailbox server.

Hi,Of course, that is required. To deploy FE, the unified namespacecan make user access any mailbox server by using one single generic URL. FE server passes the request to BE which requires the same virtual servers and virtual directoryto exist on the Back End as the Front End. The FE only is the proxy server which receives the client request and then use Active Directory to find the name of the BE server that the request to go. Next, FE will then proxy the client request to that BE server. The BE will respond to the FE which will porxy it on to the client.Please understand that the BE essentially perform the same processing when handling a client request whether it came directly or via a FE server.ThanksAllen