Fair question. The pinhole reset hasn't been helping, so I've been doing the reset with the power and light switches where you have to faff around setting the whole thing up again afterwards. I've done that at least 5 times.
My usual sequence of events is:
1. plug in USB and tap "connect" on Kobo Glo
2. open up Calibre and add some books to the reader - either epubs I've bought or downloaded from AO3 (fanfic archive), or Kindle books I've converted in Calibre
3. close Calibre
4. open Kobo software because they say you have to (sometimes this comes before 3, sometimes not)
5. either let Kobo sync or be too impatient to wait
6. eject ereader via Kobo software
7. unplug ereader (which shows no sign of having been ejected, but then it never has)
8. wait several minutes for the mise a jour
9. read "your library is empty"
10. weep bitter tears over screen
11. do the reset thing again; rinse and repeat
I have recently tried replacing steps 4-6 with ejecting the ereader from windows using the thingy in the bottom right of the computer screen, and I don't think it's misbehaved yet when I do it that way.
The problem has only happened in the last couple of weeks, so I wondered if it might possibly be down to some software update that wasn't meshing Calibre properly with Kobo. *scratches head*