Windows 10 - Remove the evil clone

After the last Windows 10 update (and after not using it for a while), I've gone through a weird issue.

I plugged in my external hard drive to work with some files and I got a pop-up saying that drive had problems, asking me whether I wanted to fix them.

I chose Fix & scan; OK- I think - it'll fix some errors and then I can use this darn disk, right?

Dead wrong.

Two identical hard drives, both having the same letter, were suddenly showing up in Windows Explorer.

Then, you might think, no big deal. Due to the error, one disk remained in the RAM.

You eject one of them and you're good.

Not so fast. The second disk can't be removed, Windows sees the two drives as  fixed hard drives.

If I eject my hard disk, they both disappear, but they come back, when I plug it back.

I tried a couple of times to reboot the system, but no avail.

After several web searches, I found out the update had introduced a new Registry key, causing Windows to detect external hard drives as removable ones, so that they're displayed twice in the Navigation pane.

For you to solve the issue, you need to navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Current Version\Explorer\Desktop\NameSpace\DelegateFolders and remove the sub-key you'll find there.

That done, the clone immediately disappeared.