Kindle USB issue - Cannot connect Kindle to PC

My kindle 3 (keyboard) was not connecting to my PC, but it did connect to any other PC.

I tried everything I found on the internet:
- restart from kindle button
- restart from Kindle settings
- checked all the USB ports in fromt (2 of them) and in the back (6 of them)

nothing worked

when i plug it in, the PC displays the Safely Remove Hardver icon in the tray, and the Kindle goes to that "USB drive mode" screen. No Kindle drive. If I "safely remove" then it still charges, the "USB drive mode" screen goes away, i can check my books, but still no kindle drive

What did I do?

I went to Device Manager, Kindle was visible (charging worked), and on Properties, I was browsing through the tabs. On the 3rd tab ("Volume") I had a Populate button, I clicked it. It showed me Kindle(E)

BUT

my E drive was a network connection (Network share), a kind of shortcut to an other computer from the LAN

i disconnected my "old" E drive, the Network Share.

Ta Da !

All the Kindle folders suddenly showed up on the E drive right there.
Case closed.

Seems like the Kindle was trying to force itself to a (taken) drive letter, not sure why.

If you ever have the same issue, if you don't see the Kindle drive in Windows File Explorer, try if you can see it in (My Computer - Manage) Computer Management - Disk Management, maybe all you need to reallocate some drive letters.