Hi All, need help here. I got Exchange 2003 Enterprise run under 2003 enterprise server with sp2. The domain server is also under 2003 enterprise sp2. All servers are Dell. The Exchange server (PowerEdge 1800) is randomly lost connection with the domain server (PowerEdge 2800) with the event 5719 This computer was not able to set up a secure session with a domain controller in domain MERCYMINISTRIES due to the following: The remote procedure call was cancelled. This may lead to authentication problems. Make sure that this computer is connected to the network. If the problem persists, please contact your domain administrator. . I can reboot to fix the issue. I changed the cable, run the diagnostic with onboard network card, and swap switch port. No error can be found. Any suggestion will help. Be Blessed! HLiu

Hi HLiu, Firstly, I would ask your attention about a known issue about TCP Chimney offload with NAT after installing Windows 2003 SP2. For more solution about the issue, please refer to below KB: You may experience network-related problems after you install Windows Server 2003 SP2 or the Scalable Networking Pack on a Windows Server 2003-based computer http://support.microsoft.com/default.aspx?scid=kb;EN-US;936594 Meanwhile, according to my experience, as this issue occurred randomly, so I also think one of possible causes is related to networking busy or bad NIC. I suggest you need confirm the issue occurred time. Does it occurs while at networking traffic time such as scheduled time for Exchange network backup etc? some situations may not occur once manually changing the networking speed mode to 100M duplex. You may need try below steps. Step : ====== 1. Open Device Manager. 2. Find the Network adapter device. 3. Right click and choose Properties. 4. In the Advanced Tab, please set the speed & Duplex to 100Mb full manually. Note: You need consult your network device Provider for the switch device port speed mode. Some basic troubleshooting logs need to collect while troubleshooting Exchange DSACESS issue ======================================================================== Please run below commands in CMD console. Please note that we need install Windows 2003 resource kit (which can be find in support\tools folder under the windows 2003 installation CD) 1. DCDIAG /v >C:\dcdiag.log 2. Netdiag /testsgetdc /v>C:\netdiag.log Note2: after running it, the Dcdiag.log and netdiag.log should be saved in the C:\, please open and check if there are any information. More information for your reference ============================ For an overview of Exchange Best Practices Analyzer Tool, refer to the following link: http://technet.microsoft.com/en-us/exchange/bb288481.aspx Download PortQryUI tool to query Exchange ports http://www.microsoft.com/downloads/details.aspx?FamilyID=8355e537-1ea6-4569-aabb-f248f4bd91d0&DisplayLang=en How to capture network traffic with Network Monitor http://support.microsoft.com/?id=148942 Regards, Jason

Jason, Thanks for your reply. Great information. These were Iwhat I did for the past few days. The connection drops were not in any busy hours. They happened in the early morning late night, or noon time.They are not in the backup time as well.I tried replaced nic card, changed cable, and switch. It still happened as before. So, at the end, I opened a support call with Microsoft. After 20 hours with over 6 support tech, they "believe" that it is the trust domin and dns didn't establish correctly. They ran dcdiag, netdiag, and Exchange Best Practices Analyzer. The support tech include connector, admin, exchange, dns and DC. Several areas were changed, too many areas and I cannot remember now It is up and runing again. I will monitor for the next few days and take some notes and document the changes as well. We will see if this is really fixed or not. Again, thank you for your informaiton. they are in my notes as well. hliu.

I am glad to hear that the server is up now. I hope it was fixed completely. if you have any update, please post it here. Thanks, Jason

Just finished the last piece of fix. It is back to normal now. The rest will be the monitor oflost connection to domain server will happen again or not. I will let you know. Thanks hliu