If you’re playing around with older OSes in the latest versions of Hyper-V, you’re missing one thing, the Integration Components (IC).
With Win10/Server2016 they no longer include this ISO as the current “supported” OSes all get their IC viaWindows Update.
You can get the IC from Hyper-V 2012/2012R2 Server, a free download, here:
https://www.microsoft.com/en-us/evalcenter/evaluate-hyper-v-server-2012-r2 ( to extract, you’ll need to mount the ISO, open the x:\sources\install.wim file with something like 7zip, browse to Windows\system32, and extract the vmguest.iso or install Hyper-V Server in a VM to get the vmguest.iso)
Or, if you’ve got a Windows 8/8.1/2012/2012R2 VM/system available with Hyper-V installed you’ll find it in the C:\windows\system32\ folder.
I’ve got a copy from Hyper-V 2012 R2 here: https://github.com/adminsecurityeu/vmguest/blob/main/Hyper-V2012R2-vmguest.iso
Hyper-V 2008 R2 here: https://github.com/adminsecurityeu/vmguest/blob/main/Hyper-V2008R2-vmguest.iso
Hyper-V 2008 here: https://github.com/adminsecurityeu/vmguest/blob/main/Hyper-V2008-vmguest.iso
No guarantees how long MS will allow it will stay up here, though it’s freely distributed with Hyper-V Server.
After installing the IC on OSes older than Windows Server 2012R2, you will still see 2 unknown devices. Per Microsoft, this is expected: https://support.microsoft.com/en-us/help/2925727/unknown-device-vmbus-in-device-manager-in-virtual-machine-for-avma
