Windows server 2008 R2 X64 Active Directory Sites and Services Replicat Now The following error occurred duringthe attempt to contact the domain controller BDC: the system detected a poosible attempt to compromise security. please ensure that you can contact the server the authenticated you TK

Hi, This problem occurs because the network firewall filters Kerberos traffic. To resolve this problem, configure the network firewall so that TCP port 88 and UDP port 88 are not blocked for either domain. If the issue persists, please also refer to the following Microsoft articles: You receive a "The system has detected a possible attempt to compromise security" error message when you try to include security settings for a user from different domain in a local domain folder http://support.microsoft.com/kb/938457/en-us The Net Logon service on Windows Server 2008 and on Windows Server 2008 R2 domain controllers does not allow the use of older cryptography algorithms that are compatible with Windows NT 4.0 by default http://support.microsoft.com/kb/942564/en-us Name Suffix Routing http://blogs.technet.com/b/askds/archive/2009/04/10/name-suffix-routing.aspx Regards,Arthur Li TechNet Community Support

Hello, if you have the firewall enabled assure that ports according to http://technet.microsoft.com/en-us/library/dd772723(WS.10).aspx are open in both directions.Best regards Meinolf Weber MVP, MCP, MCTS Microsoft MVP - Directory Services My Blog: http://msmvps.com/blogs/mweber/ Disclaimer: This posting is provided AS IS with no warranties or guarantees and confers no rights.