The Positive Periodic DC Cache Refresh for Background Callers machine setting should be configured correctly. Determines when a successful DC cache entry is refreshed. This setting is applied to caller programs that periodically attempt to locate DCs, and it is applied before the returning the DC information to the caller program. The default value for this setting is infinite (4294967200). The maximum value for this setting is (4294967200), while the maximum that is not treated as infinity is 49 days (49*24*60*60=4233600). Any larger value is treated as infinity. The minimum value for this setting is to always refresh (0). Fix: (1) GPO: Computer Configuration\Administrative Templates\System\Net Logon\Positive Periodic DC Cache Refresh for Background Callers (2) KEY: HKLM\Software\Policies\Microsoft\Netlogon\Parameters\BackgroundSuccessfulRefreshPeriod