The system must be configured to require a strong session key.

A computer connecting to a domain controller will establish a secure channel. Requiring strong session keys enforces 128-bit encryption between systems.

If the following registry value does not exist or is not configured as specified, this is a finding:

Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \SYSTEM\CurrentControlSet\Services\Netlogon\Parameters\

Value Name: RequireStrongKey

Value Type: REG_DWORD Value: 1

Warning: This setting may prevent a system from being joined to a domain if not configured consistently between systems.

Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Domain member: Require strong (Windows 2000 or Later) session key" to "Enabled".