RPC over HTTP (not HTTPS) in Outlook/Exchange 2003 environment

[punchme]

I am trying to get the RPC over HTTP mode working in an
Outlook/Exchange 2003 environment. I am trying to get it
to work with HTTP transport (not HTTPS), and all the
documentation seems to assume one would only ever want it
to be HTTPS, so I fear I'm in uncharted waters.

My server is Windows 2003 Enterprise Server running
Exchange 2003 Server plus SP1. I followed the
instructions at

http://support.microsoft.com/?id=833401

to configure the RPC service. My client is XP plus SP1
running Office Professional 2003. I installed the fix at

http://support.microsoft.com/default.aspx?kbid=331320

and
the "Exchange over the Internet" settings appear in my
Outlook 2003.

For my "Exchange Proxy Settings" in the client, I found
that the only way to get the URL to be an "

http://"

prefix (instead of "

https://")

is to use NTLM
Authentication and uncheck "Connect using SSL only".
Unfortunately, when configured in this manner, when I
start up Outlook, I am prompted for credentials and they
do not work: The prompt for credentials keeps coming back
again and again.

Looking at the Troubleshooting section of the
configuration document, reference is made to adding a
registry key "EnableRPCTunnelingUI" under the subkey
HKEY_CURRENT_USER\Software\Microsoft\Office\11.0
\Outlook\RPC . However, that "RPC" subkey doesn't even
exist on my client system. I'm not sure why mine doesn't
have it (I have Outlook Professional 2003), but all
articles on the topic speak of it as if it should
automatically be there. I'm also not sure if this is the
source of my problems, or if I'm doing something else
wrong.

Does anyone have ideas? Thanks.

--
Phil Rzewski

 

[punchme]

I got a solution to this one that works, in case anyone ever digs up this message in the archives. Someone on a public Microsoft newsgroup responded to my post over there.

-----
Add the AllowAnonymous registry value (this one goes under the RPCProxy folder).

HKLM\Software\Microsoft\Rpc\RpcProxy
Value: AllowAnonymous
DWORD: 0 or 1

0 (or value missing) = RPC connection must be over SSL
1 = Anonymous is allowed (I repeat... this is setting is *not* recommended by Microsoft for Internet facing systems. Should only be implemented in closed networks.)
-----

--
Phil

 

[JasonJ3124]

I had this same problem.

Go into IIS Manager, and open up the properties for the RPC folder in your Default Web Site. On the Directory Security tab, go to Authentication and Access Control and make sure that Integrated Windows Authentication is checked. By default, it's only set to basic authentication, which doesn't do you much good when you want to use NTLM.

Hope this helps.

-Jason

 

[JasonJ3124]

Oh, and here is a good how-to article from MCPMag.

http://www.mcpmag.com/columns/article.asp?EditorialsID=654

One nice tip from that article that is helpful in troubleshooting HTTP/HTTPS connections:
Hold down CTRL and right-click on the Outlook icon in the system tray, and select Connection Status. You can see all your HTTP/HTTPS connections listed and their stats.

-Jason