I read up to about page 9.
Have you people tried importing via the file explorer method?
- Open up file explorer with your iPhone plugged in (USB connection).
- You will see the name of your iPhone listed in the left.
- Right click the name (iPhone) and select 'import pictures and videos'.
- Then follow the instructions.
This method worked for me, instead of the Photo App method.
I was clearing out my old iPhone 7 Plus.
Yes - I have tried all suggestions so far mentioned right up to this post - every one of them, and even gone back after updating Windows and IOS and tried them again. It's great that file import worked for you at least and some others here.