Aliasing a Windows File Server

You’ve consolidated 2 servers down to 1 after hours. Great. Then you recreate all the file shares on the new server, and test mapping them using the new name. They work great.

Then in a sudden flash of brilliance, you update DNS and WINS to point the old server name at the new server, so that any scripts that still reference the old name won’t break. And that’s when you start getting this error on your clients:

System error 52 has occurred.
A duplicate name exists on the network.

Duplicate name? On the clients? Whats going on? You might check the server, and be surprised to not see any ‘Duplicate name exists’ errors anywhere. The error actually makes some sense when you think about it:

Client sends SMB request to OldServer > OldServer is an alias for NewServer > NewServer sends reply to request > Client receives reply from NewServer and not OldServer, and assumes that a 2nd machine is responding to the request, and throws the duplicate name error.

To fix this, Microsoft KB281308 tells us to add a new registry key on the server side,  HKLM\System\CurrentControlSet\Services\LanmanServer\Parameters, called DisableStrictNameChecking.  Set it to be DWORD:1, then restart the server.


If you want to access the file shares from that host using the aliased name remember to add this as well or you will have problems.

Windows Registry Editor Version 5.00