I have Server 2012 Essentials R2 configured with a regular old domain, and several Windows 8.1 machines joined to this domain.
I created a Windows 10 install USB using the Windows 10 Media Creation Tool and proceeded to upgrade my Windows 8.1 machine to Windows 10 Pro. This all went without a hitch, and as far as I can tell my machine is still connected to the domain, all mapped drives and permission are still working etc...
The only problem is that my 2012 Server Essentials can no longer see my machine, take backups, check the updates status etc.... If I open the Dashboard on 2012 and check my PC in the devices tab, it says it is unable to connect and that it may be offline. If I try a start a backup of the PC it says the same thing. When I check the properties of PC it still says it is running Windows 8.1 (obviously because that's the last thing it was running when it saw it last)
I have not been able to find anything online regarding this problem, in fact all I can find is people using the same process as me and it working fine(although none explicitly mention if Server 2012 is able to see the PC afterwards)
Any advice much appreciated.
Manually install the client connector as detailed at http://blogs.technet.com/b/sbs/archive/2015/07/23/client-connector-availability-with-windows-home-server-small-business-server-and-windows-server-essentials-for-supported-client-os.aspx
The procedure seems to be
This does make the back up and Launchpad work again It doesn't make the server correctly see the client computer - OS type / update status / security status
It is undocumented, somewhat unsatisfactory and rather laborious.