Hi, Just suspect this is a network related issue. If convenient please also verify network binding order is correct. You can also try this KB: http://support.microsoft.com/kb/948496 (Go to Exchange server 2007 => go to network card => under the name of the network card => configure => Go to Advanced TAB => Checksum offloading )Best Regards!

We are currently running Exchange 2007 SP2 RU5. Can you provide more information about the NIC teaming? I am not sure why that would be causing the errors for ADAccess. We currently have the NICs teamed on the CAS server but they are not teamed on the server hosting the mailbox role. Can you provide additional details about the checksum offload as well and how to disable it? Thank you

I am seeing a handful of MSExchange ADAccess event IDs on my Exchange 2007 CAS servers. How can I eliminate these errors? I have ran nltest /dsgetsite to verify my AD site and I am waiting to refresh the AD topology service. 1) Should I wait to refresh the service during off-hours? 2) Is there anything else I should be looking at? Thanks

What are the exact errors you are seeing?

Here are the errors below. Event ID 2501 Event Type: Error Event Source: MSExchange ADAccess Event Category: General Event ID: 2501 Date: 10/17/2011 Time: 1:07:50 PM User: N/A Computer: SERVER1 Description: Process MSEXCHANGEADTOPOLOGY (PID=1380). The site monitor API was unable to verify the site name for this Exchange computer - Call=DsctxGetContext Error code=8007077f. Make sure that Exchange server is correctly registered on the DNS server. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp. Event ID 2604 Event Type: Error Event Source: MSExchange ADAccess Event Category: General Event ID: 2604 Date: 10/17/2011 Time: 1:07:50 PM User: N/A Computer: SERVER1 Description: Process MSEXCHANGEADTOPOLOGY (PID=1380). When updating security for a remote procedure call (RPC) access for the Exchange Active Directory Topology service, Exchange could not retrieve the security descriptor for Exchange server object SERVER1 - Error code=8007077f. The Exchange Active Directory Topology service will continue with limited permissions. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp. Event ID 2601 Event Type: Warning Event Source: MSExchange ADAccess Event Category: General Event ID: 2601 Date: 10/17/2011 Time: 1:07:50 PM User: N/A Computer: SERVER1 Description: Process MSEXCHANGEADTOPOLOGY (PID=1380). When initializing a remote procedure call (RPC) to the Microsoft Exchange Active Directory Topology service, Exchange could not retrieve the SID for account <WKGUID=DC1301662F547445B9C490A52961F8FC,CN=Microsoft Exchange,CN=Services,CN=Configuration,...> - Error code=8007077f. The Microsoft Exchange Active Directory Topology service will continue starting with limited permissions. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Hi, Research and found that the possibel cause for this issue is 1) Teaming: If you have please remove the teaming 2) Checksum offload: Try to disable Checksum offload and try again. 3) update: Make sure your exchange server has the latest update. Best Regards!

Hi, Just suspect this is a network related issue. If convenient please also verify network binding order is correct. You can also try this KB: http://support.microsoft.com/kb/948496 (Go to Exchange server 2007 => go to network card => under the name of the network card => configure => Go to Advanced TAB => Checksum offloading )Best Regards!