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FunkiNATEr asked on

RPC over HTTP: NTLM Auth Not Working

I am on a laptop that has a trust relationship with my corporate office's domain, but when I log on with my user credentials away from the office and try to access my Exchange account using Outlook 2003 and RPC over HTTP with NTLM authentication, Outlook keeps asking me for a username and password.  If I switch to basic authentication, I can get in when I enter my user and password, but I don't want to have to keep doing this, as I believe NTLM auth should make this a seamless experience for me, much like I have when I am at my desk (if I understand properly how this is supposed to work).  Ideas?

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8/22/2022 - Mon

Integrated authentication has to be enabled on the RPC virtual directory on the Exchange server. If it is not, then NTLM will not work. If you have to change it then run iisreset on the server to make the change write to the metabase.

In some cases, even enabling the option will not make it work. Some firewalls will break NTLM authentication. If that is happening there is little you can do but stick with basic.


That seemed to work and it let me in once I put in my e-mail address and domain password; however, is there a way it can work without asking for the username/password at all?  Thanks for your help.

If the machine is a member of the domain, and you are using integrated authentication then you shouldn't get a prompt at all.
If the machine is not a member of the domain, or you are using basic, then a prompt will always be generated because you need to authenticate against the domain.

Experts Exchange is like having an extremely knowledgeable team sitting and waiting for your call. Couldn't do my job half as well as I do without it!
James Murphy

The machine is a member of the domain and I'm using NTLM.

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