Hi Raj, To your previous question: No, I cannot any certificate related information message, if I try to create an RPC over HTTP profile. Outlook tries to connect over RPC port (NOT through RPC over HTTP) to connect to Exchange. To your last message: Is it really true that RPC over HTTP profile can only be created? I'm disagree with you that this is a security advantage. In this case, the person who works in home office or in another company and wants to have a RPC over HTTP profile, must bring his/her computer to my LAN to have an RPC over HTTP profile!!! What a wonderful design of Microsoft!!! That is really unbelievable. I think, Steve has right that RPC over HTTP needs still port 135 to connect Exchange. If yes, this profile should be called RPC over H(alf)TTP. I didn't read in any Microsoft documents about it. It seems that Microsoft doesn't publish this "open secret"?! Or dou you know any official Microsoft document about it? Best Regards Mustafa