The Computer Browser service worked yesterday. Today, none of the computers on my LAN (three XP boxes all in the same workgroup) appear in Windows Explorer. One issue appears to be that the browser service fails to start at boot up, despite being configured as automatic. I click the start link and it starts. Stop and restart links appear in the services dialog. But no computers appear. Clicking Restart results in a stop with no start. The start link reappears. This scenario is repeatable. Any computer can be accessed by keying in the UNC in Explorer's path bar. This makes it appear (in lower case) in the network list. Exit Explorer and relaunch it, and the computer disappears from the list. Is there any way to troubleshoot this? The network troubleshooter says all is well and suggests I talk to somebody else. Surely, an OS that occupies several GB of HD space and occupies a Gig of RAM should be able to figure out how to deal with a 4 computer peered LAN. Windows 9, anyone?

That shouldn't really matter. The computer browser service is an NT legacy app. I have the computer browser service disabled in Win 7 on my network. But you must have at least one machine running the service. Have you disabled it on all your XP machines? The tool to troubleshhoot browser problems is browstat. It is in the XP support tools.Bill

So, if computer browser is not the issue, then I will rephrase the question: What tools are available for troubleshooting "network discovery"? In the advanced options, "network discovery" is set to ON. The services which the help says are required for this feature are all configured to automatic and are running. But yesterday, all the computers in the LAN workgroup disappeared from the "Network" folder in Explorer, except my computer.

Hi, Based on my research, I would like to suggest the following: 1. Please make sure that the Link Layer Topology Discovery (LLTD) has been enabled on the Windows Vista computer and the Link Layer Topology Discovery (LLTD) Responder has been installed on the Windows XP computers. Link Layer Topology Discovery (LLTD) Responder (KB922120) 2. Temporarily disable or remove all the security software (firewall, anti-virus, anti-spyware, etc.) on all the computers and check if it works. Hope this helps. Thanks. Nicholas Li - MSFT

Nicholas, Thank you for that info. The Link Layer Topology map is very nice. It even includes my switches and router. This at least illustrates that my network is working fine at the link layer. The only devices missing from the map are the NAS (which runs an embedded Linux), the network printer, and the wireless segment. (Two devices on the wireless segment show up as "other devices" with no connection. My problems are unfortunately at the session layer. That is where I need some kind of diagnostic capability. In the Windows 7 RC version, all computers in my workgroup instantly appeared under heading "Network" in Windows Explorer. (Which is to be expected, given the network topology connecting all of the computers is gigabit Ethernet) This list included the NAS. Immediately after installing the gold version of Win 7 (Ultimate x64), I had the same list. However, after reinstalling most of the applications, and transferring settings, this list no longer appears. This fact in and of itself seems to be an indication of an issue. Insofar as useful networking goes, some things work, others do not. (1) My *.rdp files work perfectly fine for operating two of the computers remotely. (2) Upon entering \\computername in Explorer, for any of the networked computers, it presents a list of all shares for that computer. I can then browse each share for all but one of these computers. (This computer happens to be one that I operate remotely using Remote Desktop. If I attempt to browse a share on that computer, a message box appears titled "Open Folder", which states "\\computername\sharename is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have permissions. (new paragraph) Not enough server storage is available to process this command." No events appear in the event log associated with this. I have tried setting IRPStackSize to 12 (0x0C), with no joy. Some other stuff, but this is enough to chew on, I think. Phil

There appears to be at least one error on the topology map produced by LLTD. There are two switches connected to each other, which is correct. There are two computers connected to each switch, also shown with the correct computers on each switch. However, the internet gateway (router) is shown connected to the wrong switch. Is this normal?

Hi, At this time, I would like to confirm you can see the Windows XP computers from the Windows 7 computer. Regarding the issue that Windows 7 cannot see Windows XP computers, it is related to Browser service and I will share the following information with you: For Windows 7 computers, please ensure "Network Discovery" is turned on in "Network and Sharing Center". Also, just for your reference, in Windows network environment, there is a service called "browser service" which is responsible for maintaining a "browser list" which is a list of computers in the network/domain. This is designed for performance purposes: every system does not need to hold a computer list for itself. Instead, the Master Browsers in the network/domain collect the computer list for the whole network, and provide the list to other systems. Therefore we can see the computer list in "Network" because the system can get the list from the master browser of that network/domain. Actually, as the "browser service" is a legacy service, if it is not need to browse the whole network computers in "Network", we can ignore safely this event. For more information regarding browser service, please refer to: TCP/IP Fundamentals for Microsoft Windows (See "Appendix C Computer Browser Service", Page 518) Troubleshooting the Microsoft Computer Browser Service Hope this helps.Nicholas Li - MSFT