The crux of the issue is that Windows Server 2012 (and above) introduce two new SIDs. The problem is that Windows 7 and Windows Server 2008 R2 clients do not know about these SIDs because when they (Windows 7 and 2008 R2) were written these particular SIDs didn’t exist. References: http://blogs.technet.com/b/askpfeplat/archive/2014/06/30/troubleshooting-windows-server-2012-r2-domain-controller-new-sids-a-real-world-example.aspx http://support.microsoft.com/kb/2830145 (Visited 232 times, … Continue reading New 2012 SIDs cause lookup issues for older clients