Windows 2000 shares: "You were not connected because a duplicate name exists on the network"

One of our elderly Windows 2000 servers had a strange problem. Even though WINS and DNS were set up correctly for the machine, trying to connect to the shares on it only worked if you connected directly to its IP address, for example:

\\127.0.0.1\randomshare

If you tried to connect directly to its name (like so):

\\ourserver\randomshare

you get the message "You were not connected because a duplicate name exists on the network. Go to System in Control Panel to change the computer name and try again." From some PCs you could browse to

\\ourserver\

but you couldn't see any shares.

The solution in this case was to patch the registry for the server in the following section:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\LanmanServer\Parameters

Create a new REG_DWORD key "DisableStrictNameChecking" and set its value to "1", then reboot.

Once the server is back up and running you should be able to browse to the shares without the error.

See http://support.microsoft.com/?id=281308 for more detail.