NTDS ISAM / NTDS Replication major issues

I am using Windows 2003 Server and also Exchange 2003. The server stops accepting logins, even if the admin accounts would not work and the password gets rejected and no one could login. I have restarted the machine, and everything seems to be running fine. Another problem is that the logs start off with an error "Timeout (30000 milliseconds) waiting for a transaction response from the NtFrs service." After that we start seeing "The Security Account Manager failed a KDC request in an unexpected way. The error is in the data field. The account name was SERVERNAME$ and lookup type 0x0."

Is there any real fix for this problem? Thanks

Below is the ipconfig /all that I forgot to mention:

Microsoft Windows [Version 5.2.3790]
(C) Copyright 1985-2003 Microsoft Corp.

C:\Documents and Settings\admin1>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : hkgmail
Primary Dns Suffix . . . . . . . : mydomain.com
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : Yes
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : mydomain.com

Ethernet adapter Local1:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Intel(R) PRO/1000 MT Dual Port
Network C
nnection
Physical Address. . . . . . . . . : 00-09-6B-89-2B-AC
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 192.168.8.17
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.8.254
DNS Servers . . . . . . . . . . . : 192.168.0.19
192.168.8.17
192.168.0.20

Could you please tell us how long this thing is happening? Was there anything changed since it was working and was it ever working at that time? I think that this issue can be caused due to the SPN problem which is a bug. You will need to install the latest support tools that came with SP1.

It seems to me that you have got an issue with the databased on this DC. Incase you have another working DC, then it will be easier to destroy this one, and then do the metadata cleanup, remove the computer account, DNS entries and server object from sites and services and then rebuild the dodgy DC and promote a new one. Or else you are going to need to go into DSRM and run some low-level database commands on the database.