We have a remote facility that's connected by a dedicated T1. The setup goes like this, from our main site we have a Cisco router, which then goes to the remote site to another Cisco router, and from there it goes through a Linksys router that is performing NAT and DHCP for the PC's there. We had to do this b/c at the time we were unsure how to forward DHCP requests through the Cisco. Basically the Linksys sees the Cisco as the internet as it's plugged into it's WAN port. Up until now this has been working, and users could access their email, the internet, and files. Now one particular user cannot access email or shared files. When she tried to access a share via UNC path she would be prompted for authentication, but when she put her username and password in she would get the message "The login was unsuccessful. The username typed is the same as the login. A DC cannot be found to authenicate the login (Paraphrased)" After many different attempts we tried removing it from the domain, which worked, but now when trying to add it back it can't find the DC.
The funny thing is, when it was still joined, she could access the internet and ping our DC by IP. Also, when trying to access shared files and being prompted for authentication, if you put incorrect info for the username and password, then the correct info on the reprompt, it would let her access the shares.
I'm truly stumped on this one.