Solution Details
What follows is a complete outline of what to do during each part of the solution process.
Verification of Corruption
If the AD on a domain controller becomes corrupted, or stops replicating to other DC's, or both, find out the root cause for this. A good starting point is to check again that the DNS is in order, and revert any manual changes that may have been made recently. Also, ensure that it is not a network-related problem—this means that no routers and routes have been changed, or firewalls re-configured, and the connection is not down. These are more often than not the main causes, and not an actual corruption.
If you can safely rule out those causes, you can use utilities such as ReplMon and DCDiag, which are included in the Windows 2003 support tools, available free from Microsoft's website or on your install CD. Although ReplMon is a graphical utility, it is pretty small, and one of the best tool for checking whether or not there are replication errors within an...
