This policy setting allows you to create an exception list of remote servers to which clients are allowed to use NTLM authentication if the "Network Security: Restrict NTLM: Outgoing NTLM traffic to remote servers" policy setting is configured. If you configure this policy setting, you can define a list of remote servers to which clients are allowed to use NTLM authentication. If you do not configure this policy setting, no exceptions will be applied. The naming format for servers on this exception list is the fully qualified domain name (FQDN) or NetBIOS server name used by the application, listed one per line. To ensure exceptions the name used by all applications needs to be in the list, and to ensure an exception is accurate, the server name should be listed in both naming formats . A single asterisk (*) can be used anywhere in the string as a wildcard character. Fix: (1) GPO: Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options\Network Security: Restrict NTLM: Add remote server exceptions for NTLM authentication (2) REG: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Lsa\MSV1_0!ClientAllowedNTLMServers