I have a Kobo Glo, lately i have been receiving the message "Oops! This document couldnt be opened" everytime i try and copy a book to my device.

I have a Kobo Glo, lately i have been receiving the message "Oops! This document couldn't be opened" every time i try and copy a book to my device. I have:

1. De authorized my device and reauthorized it,

2. uninstalled and reinstalled adobe digital editions,

3. factory reset my Kobo Glo, and0

4. restarted my computer.

None of the solutions have worked for me, it still says the same message.