hi there situation: several clients are connected to a networkinfrastructure. domain controllers are win2008, file server is win2003, db server is win2003. problem: after a few minutes (random) the network connection is aborts and there will be a database error causing disconnect. other thing, when i have opened up a file, i get an error causing the disconnect. same when i use RDP to work on a server. so, it's not specific just one protocol, which has the failures. i checked with portping and i see short disconnects for about 2 pings, must be about max 2 seconds. there are no physical disconnects, as we saw on the switches. question: so i haven't got any clue how to solve this problem. i can not find any entries in the errorlog of eventviewer. does anyone of you have some good tipps for diagnosing or knows the solution? :-) thanks for help, uerueluem

Uerueluem, There are a good number of things that can cause this type of type of problem. After making sure I have the latest network drivers, I always find it best to start by proving the OS is solid. I would reccomend doing this by booting the server into Safe Mode w/ Networking (hit F8 while booting). One thing that I need to point out here is that if you have AV on the box (specifically symantec or mcafee) they sometimes like to stay running, even when you tell them not to... awesome huh. If this happens to you, let me know and I will try to give instrustions arround this. After you reboot into Safe Mode w/ Networking I would reccomend that you use the Telnet client, from another PC, to test connections to the problem server using SMB. To do this, launch a command prompt and connect to the server by IP and Port. Here is how: Telnet <ip> 445. If the screen goes black, then you connected, otherwise you will see it fail. If this works, we know that a thrid party application is likely the cause of the problem. One way to work out which one is causing the problem (after rebooting normally) is to use MSConfig (enter name at run prompt to launch). On the services tab check the box for "hide all microsoft services". Then go through them one by one (or in programatic groups) to work out when it works and when it fails. If this fails, and we are sure that AV is not running, then there may be a problem with the OS itself. There are some articles out there showing how to reset TCP/IP, but let me caution against that, it almost never works, and when it does other problems ussualy spring up later. A clean server rebuild is your best bet at this point. Ultimately, we may need a network trace to figure out what is going. If it comes to this point and you do not have an expert in house, I put contact info below that you can reach me at. Please include the link to this thread so I have a reference. Let me know how things go. If you need extra help, you can reach us at: InitialAssist@cbfive.com See my blogs at http://www.cbfive.com/blog Don't forget to give credit where credit is due, vote this as helpful if it helped you Jared