Hi there,My Hyper-V setup stopped working properly (I am still trying to isolate the cause of this!) and my guest OS's were no longer able to access the physical network or the internet although strangely they are all still receiving DHCP assigned IP addresses (DHCP is running on the host machine)I have two NICs with Realtek based chipsets and upgraded the drivers to the latest version (6.230) but to no avail.I am now uninstalling the Hyper-V role in an attempt to redo the install but have hit a problem. The uninstall has stalled at stage 3 of 3 at 76% and it looks like a hard reset will be called for...For the record this PC is not an HP machine.RegardsAdrianIf it ain't broke - break it!

Hi, In order to isolate the issue, please help me to collect the following information: 1. Did you encounter the issue after you created the VMs or the VMs working properly some time? 2. What’s the meaning of “guest OS's were no longer able to access the physical network or the internet”, please provide the details about the issue you encountered. 3. Can you access the physical network or the internet on the Hyper-V host machine? If possible, please add an extra physical network adapter to the Hyper-V host machine, create an External Virtual Network bind to it, and then connect the VMs to this new created External Virtual Network to check whether you get the same issue. Best Regards, Vincent Hu

Thanks for the replies...I resolved the problem however here is a breakdown...1. I setup Hyper-V some time ago (like maybe 5 months ago) and while it didn't like my Realtek NICs it worked - I run two W2K3 R2 VMs and a Windows 7 VM and all was happy. Even DHCP was working (apparently this is a problem with Hyper-V and SBS)2. About 3 weeks ago the VMs started experiencing problems - from each guest operating system the network reported that only limited access was available. What this meant was the local network was invisible - the only machine showing up in the network list was the virtual machines and the server upon which they were hosted.3. I tried changing the VM network from native to legacy. I tried rebooting the VMs and the server. I tried upgrading the NIC drivers. I tried disabling all the offload settings. Nothing worked.In a fit of desparation I uninstalled Hyper-V and this is when the uninstall stuck at 76%. Following a server reboot Hyper-V continued to uninstall itself without further drama however it left the virtual network devices installed and in this state the NIC that was assigned to Hyper-V was not sending or receiving network traffic - in short it seemed like a problem in the driver stack configuration.As other people have remarked - these devices are exceedingly difficult to remove - in the end I wrote an application to do it - (essentially this utility functioned as a "temporary service" and removed the registry settings while running under the SYSTEM account but THAT is another story...)Anyway once the legacy of Hyper-V was removed and the server restarted - the NIC started relaying data-packets (confirmed by using Network Monitor incidentally)All this done - I reinstalled Hyper-V (no problems there) remembering NOT to run the Virtual Network wizard during the installNext I disabled offload on the Hyper-V NIC and the Virtual network switch and now my original Hyper-V VMs are running again - they see all the devices on the local network, they see the internet and Windows Update is working too.I think I will try to clean up the code in the removal tool I wrote as something tells me that others may find it useful and I might have reason to use it again...Hope that all helps,Regards,AdrianIf it ain't broke - break it!

Hi, The following post discussed how to remove virtual network on Hyper-V and return the physical network adapter, you can refer to: How can I enable host access on a NIC within HyperV R2? http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/thread/708aef60-05ad-40ed-af70-5ddcaf2a7a36 Best Regards, Vincent Hu