error 0x80070026 when copying files to network drives

I was on the release preview channel. I installed the latest feature update and after a restart I saw the error 0x80070026 when copying a file to my network drive.

Turns out there is a fix but you need to be in the dev channel.

I couldn't fix it so I had to go back to the previous update.

After going back to the previous update, Windows Update stopped working. There were 2 updates. When installing those I saw the 0x8000ffff and 0x80070643 "Install error". I have tried everything to fix this issue:

- Windows Update troubleshooter

- Delete the software distribution folder

- Run SFC and DISM

- and so on.

But nothing worked.

So I went back to the latest feature update and hoped the copying error will not return. Unfortunately the error was still there. Now I'm forced to build 25140 in the dev channel and indeed that fixed the copying error. 

Why there is no update for the 0x80070026 copying error in the release preview channel? Not being able to copy files to your network drive is pretty serious. I had to choose between build 25140 in the dev channel or leaving the insider program (clean install) which is very drastic.