I am attempting to use a Watchguard firebox 550e with Fireware XTM 11 to authenticate incoming traffic for RDP access. I have configured the firewall to use my domain controller for Active directory authentication with a Windows 2000 server farm and added a couple of user accounts to the users list in the firewall, but when I attempt to log onto the authentication page for the firewall, I get Logon failed. I know that the user names work and that the passwords are correct. I am also certain that I have told it to log on using Active Directory instead of the FireboxDB. I have tried using the username alone, the domain\username, and the email address. I believe that the Search base is correct (DC=mydomainname,DC=com), and I did not change any defaults for sAMAccountName (and I do not recall making any changes to those items when configuring the domain structure). Any assistance would be appreciated.