I have a similar problem and it is definitely related to
When I check here:
The resolution is to set :
1. Click Start, and then click Run.
2. In the Open box, type regedt32, and then click OK.
3. In the Registry Editor window, locate the following registry key:
4. In the right details pane, double-click DisableDFS.
The DFS client is turned off if the value in the Value data box is 1.
The DFS client is turned on if the value in the Value data box is 0.
5. In the Edit DWORD Value dialog box that appears, type 0 in the Value data box, and then click OK.
My problem is that their is no such entry for 'DisableDFS'. The DFS service is started as is the TCP/IP netbios helper
May also be relevant:See attachment when I try to run Domain controller security policy from administrative tools.
Also: I have 2 domain controllers 1, W2000 and 1, W2003. Problem existed prior to introduction of W2003 DC.