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Have you tried setting static DNS on those two machines? Make sure that the only listings are internal DNS or DCs. (I've seen some networks where people push out internal and external settings via DNS hence why I ask)
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Have you checked if they have IPv6 enabled...if so disable it and check again.
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IPV6 Disabled. &nbsp;And the DNS is static. &nbsp;(keep in mind while you are helping out, that the settings on these two machines is the same as on 18 others). &nbsp;I am thinking it is related to the unique software installed, the user knowing the admin password, ...I looked at the logs...nothing. &nbsp;Not a peep. &nbsp;but then again the machines are ok at the moment. &nbsp;I will add more when I am there and the systems are in fault condition.
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What is the unique software installed?
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This could also be a server side issue related to security. I don't know what setup you're using other than to assume, based on 18 machines, it's a single control block. Are these two machines, with the unique software they run, sending abnormally large bursts of packets at particular points in the day? Of course, that still wouldn't explain why they continue to function on the internet. Unless you have them all set up with secondary DNS external to whatever control source handles that regularly.
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they have some programs to view various video surveillance devices, I have slogged through the services, start-up programs and can't really find anything unusual. &nbsp;I don't believe they are sending large bursts of data. &nbsp;And the problem occurs at random times. &nbsp;It isn't even noticeable unless they are in the process of saving a file...say from word, to their personal network drive and they get the message that they can't access it. &nbsp;The unique software would only be a direct concern if the issue arose during its use, &nbsp;I have asked and in many instances they (the users) report they were doing nothing more than checking email, opening/closing word or excel files, browsing the web. &nbsp;On the server side I have cleared the logs. &nbsp;instructed the users to report the issue immediately and to note the time and date they notice the problem. &nbsp;I will then focus on both WS and Server event logs around those times.
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Another possibility, and it seems so unlikely, is any anti-virus software that might be blocking certain traffic for these two people. Again, it seems highly unlikely, but I've had many business clients recently with simple trust issues within their protection software. Things that would lock their printers out but the rest of their functionality was intact. So it can definitely be selective in it's doings.
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Because of the nature of the issue, one system, highly sporadic, days on end with out issue then it pops up. &nbsp;then solves itself. &nbsp;No specific event log entry to point to, no issue on server or other system with similar setup. &nbsp;I think I will make this system a priority to be replaced vs. trying to track down the problem.
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I have two workstations that are experiencing an odd problem that I am having trouble identifying and fixing.<br />
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Periodically, and randomly these two machines are losing their network domain access (the visible part of the problem is all of the mapped network drives have a red &quot;X&quot; on them), they can't access those drives, but they still have Internet Access, so the network card is fine. &nbsp;There are a couple of dozen other workstations on the same subnet, same essential setup, and NONE of the other systems experience the problem. &nbsp;Rebooting, logging off, or just waiting will fix the problem, sometimes, probably.<br />
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I am heading over to the offices now to pull pertinent log entries so save for future reference.<br />
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Right now I am thinking that there is something unique about these two systems (software, user activity) that is the source of this headache.<br />
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These are both W7 Pro, on a VM based 2008 Server.
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I have two workstations that are experiencing an odd problem that I am having trouble identifying and fixing.

Periodically, and randomly these two machines are losing their network domain access (the visible part of the problem is all of the mapped network drives have a red "X" on them), they can't access those drives, but they still have Internet Access, so the network card is fine.  There are a couple of dozen other workstations on the same subnet, same essential setup, and NONE of the other systems experience the problem.  Rebooting, logging off, or just waiting will fix the problem, sometimes, probably.

I am heading over to the offices now to pull pertinent log entries so save for future reference.

Right now I am thinking that there is something unique about these two systems (software, user activity) that is the source of this headache.

These are both W7 Pro, on a VM based 2008 Server.

2 of 20 machines, Domain Access lost, BUT NOT connectivity (Internet works 100% of time)

Networking is the process of connecting computing devices, peripherals and terminals together through a system that uses wiring, cabling or radio waves that enable their users to communicate, share information and interact over distances. Often associated are issues regarding operating systems, hardware and equipment, cloud and virtual networking, protocols, architecture, storage and management.

Networking

The Domain Name System (DNS) is a hierarchical, globally distributed system responsible for associating the name of a computer, service or other resource into an IP address for connecting to the Internet or a private network. Most prominently, it translates domain names to the numerical IP addresses needed for the purpose of computer services and devices worldwide.

The Windows operating systems have distinct methodologies for designing and implementing networks, and have specific systems to accomplish various networking processes, such as Exchange for email, Sharepoint for shared files and programs, and IIS for delivery of web pages. Microsoft also produces server technologies for networked database use, security and virtualization.