I followed the steps to show hidden files
In C:$Windows.~BT there is a DUDowload folder with a Set Up folder with setupprep.exe
There is also a Sources folder with setup.exe
I changed the compatibility for the latter inc. for all users
I deleted some programmes to leave 36.8GB free of 111GB
restarted
double-clicking setup.exe gave me 0x80070002
changing the compatibility for the file on the dvd gave 0x80070005
changing the compatibility for the file on the USB stick at least gave me an opportunity to download and install updates, but then Modern Set Up host stopped working
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now for another option
I downloaded the ISO a while ago and, before I tried to upgrade to win10, I made a system image file of my win8.1 system
Using the DVD ISO, I managed to upgrade successfully to win10 but I couldn't connect to e-mail/internet so I rolled back to win8.1
could I use the system image file, on an external harddisk, to re-set my PC back to when the upgrade to win10 worked, and update the driver for the Ethernet/realtek so that will work, or am I at risk of corrupting it so none of it will work anymore? I've not used a system image file before
or should I wait until a better version of win10 comes out, or another option?
thanks for your continuing advice