I've been running into some issues with a Windows 7 running on a Hyper-V server (2012r2 core) where it seems the network interface in Win7 is disconnecting but without errors being listed in the event viewer. I noticed that the driver that is installed in Win7 is from 6/21/2006 and I'm not able to find any updated driver. I find it hard to believe there isn't an updated driver since then? All updates have been applied through windows updates.
Is anyone aware of a more recent version of the Hyper-V NIC driver on Windows 7 running in Hyper-V?