I receive this error message the next day when i try to open my Active Directory --------------------------- Active Directory --------------------------- Naming information cannot be located because: The specified domain either does not exist or could not be contacted. Contact your system administrator to verify that your domain is properly configured and is currently online. --------------------------- OK ---------------------------

Moreover you would have ask AD queries in Directory Services for early responses and the concerning link is http://social.technet.microsoft.com/Forums/en-US/winserverDS/threads Regards, Ravikumar P

Hi, Could you please check similar kind of thread: http://social.technet.microsoft.com/Forums/da/winserverDS/thread/55e4bc99-5930-4aa9-8587-eeec80427a5f Regards, Ravikumar P

Moreover you would have ask AD queries in Directory Services for early responses and the concerning link is http://social.technet.microsoft.com/Forums/en-US/winserverDS/threads Regards, Ravikumar P

Hello, please post an unedited ipconfig /all from the DC/DNS server and a client machine so we can verify some settings.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.

Hello, please post an unedited ipconfig /all from the DC/DNS server and a client machine so we can verify some settings.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.

Hi, Before going further, would you please let know the what does the sentence open AD mean? When did you receive the error message? Please provide the detailed information about the current issue. Based on my understanding, the issue may related to the DNS name resolution issue. As Meinolf mentioned, wed better check the IP settings on the DCs, DNS servers and the client at this time to narrow down the cause of the issue. Regards, Andy

Hi, Before going further, would you please let know the what does the sentence open AD mean? When did you receive the error message? Please provide the detailed information about the current issue. Based on my understanding, the issue may related to the DNS name resolution issue. As Meinolf mentioned, wed better check the IP settings on the DCs, DNS servers and the client at this time to narrow down the cause of the issue. Regards, Andy

Hello, As I see, you have communication failures. This is generally caused by wrong DNS resolution, connectivity or ports filtering. To start, I would recommend the following: Choose a healthy DC / DNS server and make all DCs point to it as primary DNS serverMake sure that each DC has one IP address in use and one NIC card enabled: Multihoming is highly not recommendedMake sure that public DNS servers are set as forwarders and not in IP settingsMake sure that needed ports for AD replication are opened and not filtered: http://social.technet.microsoft.com/wiki/contents/articles/584.active-directory-replication-over-firewalls-en-us.aspx Once done, run ipconfig /registerdns and restart netlogon on each DC you have. If this solve your problem then make each DC / DNS server points to its private IP address as a primary DNS server and other DNS servers as secondary ones. For client computers, they should point to internal DNS servers as DNS servers. This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner 2010 / 2011 Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Applications Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows 7, Configuring Microsoft Certified Technology Specialist: Designing and Providing Volume Licensing Solutions to Large Organizations Microsoft Certified IT Professional: Enterprise Administrator Microsoft Certified IT Professional: Server Administrator Microsoft Certified Trainer

Hello, As I see, you have communication failures. This is generally caused by wrong DNS resolution, connectivity or ports filtering. To start, I would recommend the following: Choose a healthy DC / DNS server and make all DCs point to it as primary DNS serverMake sure that each DC has one IP address in use and one NIC card enabled: Multihoming is highly not recommendedMake sure that public DNS servers are set as forwarders and not in IP settingsMake sure that needed ports for AD replication are opened and not filtered: http://social.technet.microsoft.com/wiki/contents/articles/584.active-directory-replication-over-firewalls-en-us.aspx Once done, run ipconfig /registerdns and restart netlogon on each DC you have. If this solve your problem then make each DC / DNS server points to its private IP address as a primary DNS server and other DNS servers as secondary ones. For client computers, they should point to internal DNS servers as DNS servers. This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner 2010 / 2011 Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Applications Infrastructure, Configuration Microsoft Certified Technology Specialist: Windows 7, Configuring Microsoft Certified Technology Specialist: Designing and Providing Volume Licensing Solutions to Large Organizations Microsoft Certified IT Professional: Enterprise Administrator Microsoft Certified IT Professional: Server Administrator Microsoft Certified Trainer