Inksky
You safely ejected your Kobo from your computer — the operating system confirmed it — but when the Kobo finished processing new content, your library was empty or showing a “database corrupted” error. This is one of the most reported Kobo issues, and while it’s alarming, it’s usually fixable without losing your books or reading progress.
Why this happens
Kobo uses a SQLite database (stored as KoboReader.sqlite in the .kobo directory of the device) to track every book, annotation, reading position, and collection. When you connect via USB, the database goes dormant. When you eject, the Kobo remounts its storage and runs a process that scans for new books and updates the database. If anything interrupts that process — a failed USB handoff, a file system inconsistency, or a corrupted book file — the database can enter an unrecoverable state. The underlying books are still on the device, but the database that tracks them is broken.
Before you try anything: back up the database
Connect your Kobo to a computer and navigate to the .kobo folder (you may need to enable hidden files in your file manager). Copy the entire .kobo folder somewhere safe. Even if the database is corrupted, having the bad copy gives you options — particularly if you decide to manually extract reading positions later using Calibre’s Kobo Utilities plugin.
Fix #1: Log out and log back in
This is the nuclear option that works for most users. On your Kobo, go to Settings → Accounts → Kobo → Sign Out. The device will factory reset the database portion of the firmware, but it does not delete your sideloaded books from the storage partition. When you sign back in, the Kobo rebuilds the database from scratch, reprocessing all books already on the device. Your reading progress for sideloaded books will be lost (unless you restore from a Calibre backup), but Kobo Store purchases will re-sync with your account.
Fix #2: Use Kobo Utilities to restore from Calibre
If you manage your library with Calibre and have the Kobo Utilities plugin installed, you likely have database backups. Connect your Kobo, open the Kobo Utilities plugin in Calibre, and select Database → Restore Database. Choose the most recent backup. After the restore, eject the Kobo and let it process — your library, collections, and reading positions should return to the state of the backup.
Fix #3: Manual SQLite repair
If you’re comfortable with a terminal, you can attempt a direct SQLite repair. Copy KoboReader.sqlite from your device to your computer, then run:
sqlite3 KoboReader.sqlite "PRAGMA integrity_check;"If the output shows errors, dump and rebuild it:
sqlite3 KoboReader.sqlite .dump | sqlite3 KoboReader_repaired.sqliteReplace the original file on your Kobo with the repaired version and safely eject. This method preserves sideloaded reading positions better than a logout.
Prevention
The Kobo Utilities Calibre plugin can automatically back up your database every time you connect. Enable it under Kobo Utilities → Store → Store on each connection. For manual users, the most reliable way to avoid corruption is to wait 30 seconds after the Kobo’s “Connected and Charging” screen appears before ejecting — this ensures all USB write operations have completed.