In Calibre, the On Device column is empty

[meRobs]

I have a Kobo Forma with ePubs loaded, yet in Calibre none are shown (as a tick) in the On Device column. Even a freshly side-loaded book is not shown.

Calibre sees the Forma via a USB connection to my PC using Windows 10.

I first noticed the issue when attempts to read ePubs in Forma failed because of a faulty authorisation in ADE. Even when this was resolved by reloading the ePubs, after being re-converted to ePub in Calibre, the files were not shown in the On Device column.

A related issue may be that when the Forma is connected to a USB socket with Calibre open, an "Error communication with device" warning pops up. The details of this are:

calibre, version 7.4.0
ERROR: Error: Error communicating with device
CorruptError: database disk image is malformed
Traceback (most recent call last):
File "calibre\gui2\device.py", line 104, in run
File "calibre\gui2\device.py", line 558, in _books
File "calibre\devices\kobo\driver.py", line 2028, in books
File "C:\t\t\apsw-42s16m2x\src\cursor.c", line 240, in resetcursor
apsw.CorruptError: CorruptError: database disk image is malformed

I hope someone will offer some advice
Thank you
meRobs

[mbovenka]

The database on your Forma is damaged. What you can do is log out of your account on the Forma and log back in. That will rebuild the database, but you will lose your annotations (if you have any) and your reading stats.

[ownedbycats]

Known firmware glitch. The database doesn't always close itself properly. Mostly happens if you connect with a kepub open, but there's other circumstances that can trigger.

Restore DB from backup or logout/login. The latter will re-import all sideloaded books so you'll lose reading positions and annotations and the like.

For prevention: use Kobo Utilities to auto-backup the db. Make sure you're on the home screen before connecting, you may want to reboot the device to be safe.

[meRobs]

Originally Posted by mbovenka

The database on your Forma is damaged. What you can do is log out of your account on the Forma and log back in. That will rebuild the database, but ....

Thanks for this solution. However, I can find no way of logging out on the Forma or of logging in !!

Pardon my ignorance but I do need more help.
Thanks

Note: looking at my notes, I discovered that I did initially in 2019 used WiFi to sign in (to what?) and then > Manage Books, etc and then turned off Wi-Fi. I don't know how I did it but I also de-registered on the Forma !? Currently Settings on the Forma look nothing like what my early notes state.

[ownedbycats]

Originally Posted by meRobs

Thanks for this solution. However, I can find no way of logging out on the Forma or of logging in !!

Pardon my ignorance but I do need more help.
Thanks

Assuming it's the same as Libra H2O, go to homescreen then More > Settings > Accounts.

[meRobs]

Originally Posted by ownedbycats

Assuming it's the same as Libra H2O, go to homescreen then More > Settings > Accounts.

Thanks. I tried Home > More > Settings > Accounts, then under Kobo was 'Sign out' with my email as user ID. I am reluctant to try this because I went to www.kobo.com and tried to sign in with my user ID and it failed to accept the pswd I had initially used. So, I clicked 'Forgot password" and entered a new one which finally got me to Kobo.

The other option I found was Settings > Devise Info > Advanced > Repair your Kobo account. However, this may also lead to disaster.

Still not sure I can log out.

In any case, log out of what? Forma? Kobo?
I'm confused.

[DNSB]

You will be signing out of your Kobo account on your Forma. This will replace the database with a blank one but it will not remove your sideloaded content which will be re-imported after you sign in again. As long as you have your Kobo user ID and password, you should be able to sign in again on your Forma.

The other choice to repair the database is the Factory reset option just below Repair your Kobo account in the Device information menu. If you type devmodeon in the search box, you will get an extra item in the Device information menu called Developer options. That also has a Factory reset option which is the full factory reset and will reset your Kobo back to it's factory firmware. This last option is like the manual factory reset and pretty much a last ditch option.

There is a know issue with 4.38.21908 where the database(s) are not being properly closed before connecting which leads to database corruption, another common reason is unplugging your Kobo from the computer without safely ejecting.

My workaround for the open databases has been to restart my Kobo before connecting to my computer. NickelMenu makes this as painless as possible.

[meRobs]

Thanks very much David (DNSB), mbovenka and ownedbycats. Excellent!!
I went to Home > More > Settings > Accounts > Kobo, where my user ID (email) was given beside 'sign out'. This I clicked, which caused Forma to blank out while it did its bit.
Then, I had to start Forma from scratch by choosing my language and choose whether I wanted to proceed via WiFi or not.

I chose not to, so I had to connect to the PC via USB, go to Kobo.com and download the Kobo Desktop. This asked that I sign in, which I did.

This triggered some configuring of the Forma, installation of dictionaries, etc, and asked whether I wanted to Sync (upload purchased books) or Eject the Forma. I chose the latter.

Perfect !!
Books previously installed were still present and they now appeared in Calibre in the 'On Device' column. Excellent.

Thanks again folks.