You were not connected because a duplicate name exists on the network, Go to System in Control Panel

Description

After installing a new Windows 2008 server with the name TESTSERVER2 and modifying %windir%\system32\drivers\etc\hosts or adding a DNS CNAME/A entry for TESTSERVER, you get the following error when trying to connect to \\TESTSERVER:
"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".



Solution

On the new Windows 2008 server (TESTSERVER2):

  • Open Regedit.exe
  • Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters
  • Add a registry DWORD key called "DisableStrictNameChecking" set it to "1".
  • Restart the "Server" service (net stop server && net start server).

    SETSPN -a host/alias_name targetserver
    SETSPN -a host/alias_name.contoso.com targetserver      

    • Affected software:

    Microsoft Windows 2008
    Microsoft Windows 2008 R2