A few days in and I have solved the few problems I have had
Can apply update Security Update for Windows 10 for x64-based Systems (KB3074683)
My system tried to apply the KB3074683 patch a couple of time, rolling it back each time. A search of the forums found the answer to this one. As in the forum post I have an Nvidia video card, in fact it caused the problems during the update, so the fix was to delete the UpdatusUser registry entry under HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionProfileList.
Once this was deleted the update applied without an issues.
Windows Defender won’t start
Every time my PC started I got the error that Windows Defender would not start.
After much searching and fiddling with settings, it turned out this was a red herring. Defender was not starting as I had another AV product in place System Center End Point Protection, just as the dialog said. End Point Protection is installed by our IT team as part of our standard setup. So the actual issue was that the Defender tooltray app was trying to autostart, giving the error as it failed to connect to the background services which were not running. Strange as this appeared not to be an issue for Windows 8.1.
The answer was to use SysInternal AutoRuns to disable the loading of the tooltray application.
Can access a Data DeDup’d disk
On Windows 8.1 I use the Data DeDup hack on one of my disks that I use for Hyper-V VM; I got 71% disk space saving as there is so much common data between the various VMs. At the time of writing I could not find a matching set of DSIM packages for Windows 10, they need to come from the equivalent release of Server 2016, which is still in CTP/Preview.
After some fiddling with feature packs from preview builds, I decided to just stop using Data DeDup feature for now. So I attached my disk to a 8.1 machine with DeDup enabled, copied the contents off, re-formated the disk and the replaced the data. then put the disk back in my laptop.
I do hope Microsoft choose to add Data DeDup to Windows 10 in the future, it is of great use to me and anyone else who uses plenty of local VMs.
So I think I am there now, let us see how reliable it is day to day.