I have a Kobo Glo & a Dell PC the runs on Windows 10
I fixed this infuriating by problem following those steps:
PC:
- Uninstall Adobe Digital Editions (ADE)
- Reinstall ADE (make sure it's the 3.0 version)
- Erase PC authorization while in ADE: Press Ctrl + Shift + D
- Reauhtorize it.
- Re-download the borrowed ebooks
Kobo:
- Deautorize it in its "Settings" menu
- Connect to the PC
- Open ADE 3.0 on PC
- Open the re-dowloaded books in ADE
- Authorize the Kobo
- Copy the eBooks to the Kobo using ADE software
- Close the ADE program
- DO NOT eject the Kobo from PC, simply unplug it
This worked for me