hi,I have a serious problem with routing in windows server 2008 enterprise edition.a few specs first:The machine i have the problem with is a virtual machine in hyper-v. The host machine is a DELL PowerEdge 2950III with 2008 Servercore installation. There is one network interface for the external net and one interface for the internal net. according to this i created two virtual networks bound to the respective network interface (vmnet1 and vmnet2). There are two more network interfaces one the host. One of thoese is used for managing the host.The VM i am talking about has two processors, 4GB Ram and two network cards assigned.On the external network interface all protocols except IPv4 are deactivated. An public IP and a Gateway is configured.On the internal network inteface all (common) bindings/protocols except IPv6 are activated. An private IP, NO gateway but DNS is configured.A persistent route pointing to a branch network also exists. It is routed over a local IPsec Router.Now, the Problem is, that after some time the routing table changes. The routes for the network-id and broadcast of the internal network interface are just lost. As a result of this, access to the internal network is no longer possible... The external network and even the branch network are accessible without problems.If I reboot or just change some settings on the internal network card the routes are restored and I have access to the internal network againg for a few hours.Things already tried: Disable EnableDeadGWDetect, disabled IPv6, played around with protocol bindings.routing tables when everything works fine:IPv4RouteTable===========================================================================ActiveRoutes:NetworkDestinationNetmaskGatewayInterfaceMetric0.0.0.00.0.0.080.yyy.xxx.9780.yyy.xxx.11126180.yyy.xxx.96255.255.255.224On-link80.yyy.xxx.11126180.yyy.xxx.111255.255.255.255On-link80.yyy.xxx.11126180.yyy.xxx.127255.255.255.255On-link80.yyy.xxx.111261127.0.0.0255.0.0.0On-link127.0.0.1306127.0.0.1255.255.255.255On-link127.0.0.1306127.255.255.255255.255.255.255On-link127.0.0.1306172.26.16.0255.255.255.0192.168.109.254192.168.109.1117192.168.109.0255.255.255.0On-link192.168.109.111261192.168.109.111255.255.255.255On-link192.168.109.111261192.168.109.255255.255.255.255On-link192.168.109.111261224.0.0.0240.0.0.0On-link127.0.0.1306224.0.0.0240.0.0.0On-link80.yyy.xxx.111261224.0.0.0240.0.0.0On-link192.168.109.111261255.255.255.255255.255.255.255On-link127.0.0.1306255.255.255.255255.255.255.255On-link80.yyy.xxx.111261255.255.255.255255.255.255.255On-link192.168.109.111261===========================================================================PersistentRoutes:NetworkAddressNetmaskGatewayAddressMetric172.26.16.0255.255.255.0192.168.109.25420.0.0.00.0.0.080.yyy.xxx.97Default===========================================================================routing table with lost entries:IPv4RouteTable===========================================================================ActiveRoutes:NetworkDestinationNetmaskGatewayInterfaceMetric0.0.0.00.0.0.080.yyy.xxx.9780.yyy.xxx.11126180.yyy.xxx.96255.255.255.224On-link80.yyy.xxx.11126180.yyy.xxx.111255.255.255.255On-link80.yyy.xxx.11126180.yyy.xxx.127255.255.255.255On-link80.yyy.xxx.111261127.0.0.0255.0.0.0On-link127.0.0.1306127.0.0.1255.255.255.255On-link127.0.0.1306127.255.255.255255.255.255.255On-link127.0.0.1306172.26.16.0255.255.255.0192.168.109.254192.168.109.1117192.168.109.111255.255.255.255On-link192.168.109.111261224.0.0.0240.0.0.0On-link127.0.0.1306224.0.0.0240.0.0.0On-link80.yyy.xxx.111261224.0.0.0240.0.0.0On-link192.168.109.111261255.255.255.255255.255.255.255On-link127.0.0.1306255.255.255.255255.255.255.255On-link80.yyy.xxx.111261255.255.255.255255.255.255.255On-link192.168.109.111261===========================================================================PersistentRoutes:NetworkAddressNetmaskGatewayAddressMetric172.26.16.0255.255.255.0192.168.109.25420.0.0.00.0.0.080.yyy.xxx.97Default===========================================================================(192.168.109.0 and 192.168.109.255 missing)ipconfig/allWindowsIPConfigurationHostName............:ts3PrimaryDnsSuffix.......:VVVV.deNodeType............:HybridIPRoutingEnabled........:NoWINSProxyEnabled........:NoDNSSuffixSearchList......:VVVV.deEthernetadapterIntern:Connection-specificDNSSuffix.:Description...........:MicrosoftVirtualMachineBusNetworkAdapter#2PhysicalAddress.........:00-15-5D-70-06-0CDHCPEnabled...........:NoAutoconfigurationEnabled....:YesIPv4Address...........:192.168.109.111(Preferred)SubnetMask...........:255.255.255.0DefaultGateway.........:DNSServers...........:192.168.109.100172.26.16.4PrimaryWINSServer.......:192.168.109.100NetBIOSoverTcpip........:EnabledEthernetadapterExtern:Connection-specificDNSSuffix.:Description...........:MicrosoftVirtualMachineBusNetworkAdapterPhysicalAddress.........:00-15-5D-70-06-0DDHCPEnabled...........:NoAutoconfigurationEnabled....:YesIPv4Address...........:80.yyy.xxx.111(Preferred)SubnetMask...........:255.255.255.224DefaultGateway.........:80.yyy.xxx.97NetBIOSoverTcpip........:EnabledAny Ideas??