Error communicating with device

[MarkWillCry]

After a year of using calibre, I have acquired a new device and, therefore, a new error that gives me following details:

calibre, version 9.13.0
ERROR: Error: Error communicating with device

database disk image is malformed

Traceback (most recent call last):
File "calibre\gui2\device.py", line 107, in run
File "calibre\gui2\device.py", line 593, in _books
File "calibre\devices\kobo\driver.py", line 2390, in books
File "C:\t\t\apsw-39uykmzm\src\cursor.c", line 223, in resetcursor
apsw.CorruptError: database disk image is malformed

I have attempted:
"turning it off and on again" a couple of times
updating calibre
updating plugins
going to the previous version of calibre
returning to the current version
deleting driveinfo and metadata files

However, nothing changed.
Any guesses on what will finally fix this?
Thanks for help!

[kovidgoyal]

https://manual.calibre-ebook.com/faq...-touch-glo-etc

[theducks]

The database on the Kobo is corrupt. You need to sign it out the Kobo account, then sign back in.
You will most likely lose your reading positions unless you left WiFi on and it had synced with your account.
OTOH if you use Kobo Utilities, and have it save copies of the older DB, you could restore from a older one.

Always Eject and wait for the Kobo to settle (it shows 'Processing' if you added A BOOK) back on the Library screen. DB updates (series and stuff need to get done )

[Dal Bhat]

Threads like this one have made me shy about ever getting a Kobo device. Seems as though they are failure prone. I did see in Kovid's link that they have buggy firmware.

I've been wondering what to do if and when my Kindle craps out. I looked at the Kobo Clara and it appeals.

For a Clara, my use case would be to download epubs from the library, open in calibre to get the font I like and maybe tweak the cover, and then sideload to the device.

Do I need a Kobo acct to use one? Kobo Utilities, often mentioned here. Would I want that for how I'd use it?

[DNSB]

You might want to check when Kovid made that comment about Kobo software being buggy. It's been a few years.

You can set the font being used to display a book on the Clara. Unless the CSS in the ePub forces a font, you can use any font you want. If there is a specific font you want to use that is not in the Kobo factory font set, it is trivial to add a font.

To download ePubs from the library, the easiest way is to have a Kobo account which allows you to sync the books OTA if Kobo's copy and the library copy have the same ISBN. Otherwise you can use ADE or the ACSM plugin for calibre to download the book from the library supplied .acsm file. For your workflow, you could add SideloadedMode=true under the [ApplicationPreferences] header.

See message #9 in the Firmware 4.31.19086 thread for more information.

Personally, I find the Kobo Utilities plugin very handy. It allows you to do backups of the databases and other important files—I have it set to do this the first time I connect to calibre during a day.

Yes, they are more prone that a Kindle to having database issues if you do not safely eject. OTOH, using the Kobo Utilities backup allows you to recover from a database corruption very easily.

Unlike many other ereaders, there is no need to jailbreak or root a Kobo. They are open Linux devices. This has the advantage of allowing users to modify the database contents, etc. It has the disadvantage that you can more easily break your Kobo but, if nothing else, you can resort to a factory reset.

Many of the older Kobo devices have a removable µSD card. This has advantages in being to remove and re-image the card. OTOH, µSD cards, especially the older units, have relatively short write lifetimes. This is one of the reasons that Kobo has been switching to using eMMC for storage.

[Dal Bhat]

Helpful. Thank you.

[Sirtel]

For my part, I can add that with 3 Kobo devices in 7 years I have never had a database corruption or any other failure. I do eject them safely, always.

There are a few minor bugs, but nothing that has made me regret getting a Kobo device. I far prefer them to Kindles, which I previously used.

[JSWolf]

The latest Kindle firmware have more bugs now then Kobo.

[Dal Bhat]

Originally Posted by Sirtel

For my part, I can add that with 3 Kobo devices in 7 years I have never had a database corruption or any other failure. I do eject them safely, always.

One thing I read/saw several times while looking at the Kobo sideloading issue was that, after sending an epub from calibre to the device, a SECOND eject is required in order to have the book register correctly on the Kobo.

Is that true/still the case?

[PeterT]

The 2nd connect us required for data such as Series to be stored in the Kobo database.

The database row where Series info is stored is created during the Importing of the book on the Kobo so can't be stored during the initial Calibre session.

There is a Kobo mod available from pgaskin called NickelSeries https://pgaskin.net/kepubify/ns/ that handles the adding of the Series info without a reconnection.

[theducks]

Originally Posted by Dal Bhat

One thing I read/saw several times while looking at the Kobo sideloading issue was that, after sending an epub from calibre to the device, a SECOND eject is required in order to have the book register correctly on the Kobo.

Is that true/still the case?

Yes
Pass 1 adds the book and makes the Title-Author entries
Pass 2 adds Series and some other metadata

The reason is the database entry is what it reads from the book (processing... step) upon eject.
Until the entry has been made, there is no place to land the additional data.

[Sirtel]

Originally Posted by Dal Bhat

One thing I read/saw several times while looking at the Kobo sideloading issue was that, after sending an epub from calibre to the device, a SECOND eject is required in order to have the book register correctly on the Kobo.

Is that true/still the case?

As PeterT said, the second connection is not required for the books themselves, but for additional data, like the series information. I can't recall right now if it's also required for collections and subtitles or not.

NickelSeries eliminates the need for the second connection, but personally I haven't bothered with it. I usually transfer quite a lot of books in one session and so don't connect my Kobos very often, and connecting twice doesn't take all that much time. If I loaded books every few days I might think differently.

[PeterT]

Collections are added on the initial connection; they're stored in a separate table (which I think is indexed by the file name / path of the book on the device which is known when the book is transferred).

[Dal Bhat]

Originally Posted by theducks

Yes
Pass 1 adds the book and makes the Title-Author entries
Pass 2 adds Series and some other metadata

The reason is the database entry is what it reads from the book (processing... step) upon eject.
Until the entry has been made, there is no place to land the additional data.

Nothing else needed from calibre on the second connect? After ejecting after Send to Device in Pass 1, pull the cable and then plug it in again. At that point, simply eject to complete Pass 2.

Is that the drill?

[Sirtel]

Originally Posted by Dal Bhat

Nothing else needed from calibre on the second connect? After ejecting after Send to Device in Pass 1, pull the cable and then plug it in again. At that point, simply eject to complete Pass 2.

Is that the drill?

The correct sequence is:
1) Eject, but don't pull the cable
2) Wait until the books have been imported (there's a specific screen displaying this)
3) Pull the cable
3) Plug it in again
4) Wait until all the calibre jobs have been finished
5) Eject
6) Pull the plug