Here's my scenario: We've been running Windows 2003 server for over a year (fresh install, new box, no upgrade from previous OS.) From day 1, it was designated as a Domain Controller. Works like a champ. We get mail etc, we're happy. NOW-- I want to join an XP Pro machine to this Domain, I get a very non-descript error message: "The specified server cannot perform the requested operation". I'm a member of the Administrator's Group on the XP Pro machine. I go to the Control Panel, Computer Name tab, click "change", change the radio button from Workgroup to "Domain" enter in the name of the Domain (xxxxxxx.xxx). Click "Apply". Wait a minute or two then I get: "The specified server cannot perform the requested operation" Server is in a remote location. Its reached through a IPSec VPN tunnel to a router on our LAN. The tunnel is functioning, because I can mount remote volumes, etc. I just can't join the Domain. What am I overlooking? I'm going crazy!

Hi, A couple of things spring to mind, 1 Has the PC been added in the Active Directory Users & Computers? 2 Is the time the same as the DC? This might cause this error, seem this happen before, was doing my head in, till I noticed the time was 3 minutes out from the DC Hope this helps

Is there a firewall between the locations and can it forward Ipsec traffic? See the links below for details: http://support.microsoft.com/default.aspx?kbid=233256 http://www.sometips.com/tips/microsoft/223.htm