[wingmongyee]

Mine is not a Clara, but I've had the problem of corrupted databases with my Glo HD for a year more or less. It started going wrong out of the blue one day. Every second connection to Calibre, the database would be corrupted.

I got used to back up the database every time I could connect successfully to Calibre. I backed up the database by copying the KoboReader.sqlite file manually using file manager. Almost every time I transferred books to the device, the database would get corrupted after the first disconnection. Then once I had replaced the database with the backed up one, it would be fine until I transfered more books.

Anyway, I tried everything I could think of, and all suggestions I found on this forum, but nothing worked. I tried different USB cables but it didn't help. I thought maybe I had too many books on the device - over 1000 and the database, which was nearing 900 MB, was too big. I tried reducing the number of books. The database dropped to the 500MB mark but it didn't help. Finally, I thought the problem may have been with Calibre or with the Glo HD itself. I thought maybe the 32 GB SD card I had installed on the Glo HD years ago was damaged.

In any case, as soon as I installed Firmware 4.32.19501, the problem magically vanished. Immediately!

I haven't had a corrupted database once ever since. It's been almost a month and I connect to Calibre and transfer books almost every second day. So it appears the problem was never with the hardware or with Calibre or the manner of connecting. I assume the problem must have started after a firmware update a year or two ago but I didn't realize it at the time.

I never associated the corrupted database with a particular firmware, until the problem was fixed immediately following the latest firmware update. I kept reading the forum in the last month to see if anyone would mention an experience similar to mine but no one did as far as I could see although there's quite a few mentions of corrupted databases.

Please note that I always update manually to the latest firmware as soon as I find out on this forum that it's been released. So I don't know after which firmware the problem started but I can confirmed I installed all the updates, 4.26, 4.30, 4.31 as they were released and the problem disappeared only with 4.32.

So based on my experience, if someone has problems with corrupted databases, I highly recommend you install Firmware 4.32.19501.

After having had problems for so long and considering getting a new ereader, this new firmware which fixed the problem has given my Glo HD a new lease of life !!!

Also, I don't know if it matters but my books are in ePub format in my Calibre library and they get converted to KePub on the fly with the KoboTouchExtended driver when I transfer them to the device.

Hope sharing my experience helps. Cheers.