I solved my own problem, partially, but there is still something I don't understand. My problem was in trying to use the Secure authentication type in my Windows app. When I changed the authentication type to None (which in Windows parlance means a simple bind) it worked. All of the entries I had made for allowing my specific host access, and permissions I had granted the account (adding the user to the Domain Admins) were unnecessary. However, what I can't figure out is how to use any authentication that is stronger. I presume that the Windows None/simple bind equates to Plain. My supported sasl mechanisms are: external, plain, gssapi, digest-md5, cram-md5, and anonymous. Do I need to add to this list to communicate via stronger authentication with my Windows app, and if so how do I add to this list? Thanks, -Mont <div>On 11/12/05, Mont Rothstein <<a href="mailto:mont.rothstein@gmail.com">mont.rothstein@gmail.com</a>> wrote:<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> I can't authenticate to my directory server from another machine. My directory server is running on RedHat ES4. I am trying to use Secure authentication (NTLM?) from a Windows C# .NET application. I suspect my problem is one of incorrect configuration on the directory server side. I can access the directory server from the Windows app using anonymous access. I created a user in the directory server and added that user to the Directory Administrators Group's ACI. I also added the IP address of the machine I am trying to communicate from to the Hosts list in the Directory Administrators Group ACI. I can login to the console using my user (uid=mont,ou=people,dc=foray,dc=com) on my Linux server. I have tried logging in from the Windows app using both the full RDN and simply the user name "mont". Neither work. Any ideas as to what needs to be done to enable authentication from a remote machine would be greatly appreciated. Thanks, -Mont </blockquote></div>