Perform a search in AD Users and computers for the account in question. All duplicates including the original will show up. Delete all but the original to get rid of the error.
Depending on the network topology, this problem can also be caused by Active Directory replication issues between two or more servers. Verify that AD is replicating correctly and check in Sites and Services to ensure that the links are all there between the domain controllers. Assuming replication is happening correctly, manually verify that the account is not showing on any global catalog or AD servers in general. If that does not work, look for errors in the event log that might refer to that user's SID. If there is a SID listed for that user account, schedule the regedit.exe program in the command line (example at 9:30 /interactive "c:\winnt\regedit.exe") browse to the SAM key, search for that particular SID and delete it. Perform this process on each server. The reason you schedule the regedit program is so it runs with elevated privilege allowing access to the normally restricted SAM key. If there is no event related to the user's SID, find a utility that will show it and try to fix the problem.
shows information on Replication collisions in Windows 2000.
If the conflicting names are computer names and you are using an imaging software like Ghost then to fix these error you have to run the sisprep.exe before deploying the image.
You have a double entry in the Active Directory and need to delete one of them. (the message indicates which one of them).
From MS TechNet website:
"Fixing All Account Collisions by Examining the Event Logs for 12292 Events:
Object collisions are normal occurrences in a multi-mastered database environment where the rate of change is high and where the number of database replicas is also high.
The most common type of object collision in an environment occurs with computer account objects. A typical scenario is that a user joins a computer to a domain while talking to one domain controller, then immediately tries to use that computer object when talking to a different domain controller located somewhere else. Before replication resolves the discrepancy, the user then retries the join operation while talking to a different domain controller. The result of this sequence of events is a collision between two identically-named objects.
Active Directory recognizes these collisions and generates a 12292 event in the system event log. Active Directory will continue to generate these events until the situation is manually resolved by an administrator. Administrators should check for the 12292 events on a weekly basis, and resolve them by renaming or deleting the offending objects, which are described in the event text."
...not very useful, but at least acknowledged by Microsoft.