I tried to search for any other post having the same issue but it kept timing out so I'm creating a new post. Sorry if it's been duplicated.

I have a dev installation on a webserver and have AD authentication set up on it and it works fine. I have a duplicate of the dev site installed on my local machine and I'm trying to set up AD on it and it just doesnt want to do it for some reason. I've got everything set up exactly the same except for the actual url or the site. so instead of http://my-dev.domainname.com I have http://localhost:85/mydev/ for the domain names. all LDAP settings are the same for each installation. On the web server it accepts everything, on the local it fails saying invalid username and password. I've been able to run LDAP queries with the same username and password in a LDAP Browser that I found so there isn't any network restrictions as far as I can tell. I have read access to AD so in theory I should be allowed to access it the same way as the web server.

Has anyone else run across this and how did you fix it?

DNN version 5.1.0 with the included AD provider. I didn't actually duplicate it exactly, I did a fresh install on my local and installed the same modules and custom modules as I have on my dev box.

When I put in the attributes for the AD Settings it fails on my local but passes on my dev box. Same credentials, domain and everything. In my LDAP Browser I'm able to view all ad attributes from my local which makes it even more confusing and tells me that there is some sort of error with the application or DNN or IIS.