This further reinforces why I've fortunately never had to --- and don't ever want to --- use UWP apps. It seems like one horrible design decision after another.

On the other hand, explorer.exe seemingly wants to crash or hang semi-regularly, especially when accessing network drives, and needs to be killed and restarted to regain control.

Can someone explains why explorer crashes when dragging files (unintentionally) over an offline mapped network drive?

I feel like this is a basic thing that should have come up in testing.

Network filesystems seem to be one of those things that's remarkably tricky to get right; my experience with that on Linux hasn't been much better, i.e. mounted drives that have become disconnected can cause anything from tens-of-minutes-long waits to forever hangs. I think it's a tension between giving up too easily (and thus you get errors in applications whenever the network is even slightly intermittent) and trying too hard to reconnect (permanent hangs, in the case of infinite retries.)

Seems to be working fine on my machine.

I went to Task Manager, details tab; found explorer.exe (there was exactly 1) and killed it

Hit File -> Run New Task; Entered "explorer"; hit Enter

Switched to Mail and clicked a link in one of the emails - it worked.

>Killing and restarting explorer.exe on Windows 10 is not supported

so what are you supposed to do if explorer hangs or freezes?

That's the question, right? The official answer appears to be "it can't/doesn't happen" ... and when it does, you really do have to reboot.

Unfortunate. That exact situation has happened to me multiple times on win7 and killing and restarting explorer.exe always seemed to work. Really poor systems design from Microsoft here