The KoReader app won't open

[eudesmdcf]

Device: Kindle
KOReader version: 2025.08

Model and firmware version: Kindle Paperwhite (11th Generation)

I jailbroke my Kindle in August 2025 (approximately—I don’t know the exact version of my Koreader), but since then I haven’t had any problems, except for one time when my Kindle froze and I had to restart it. However, today, when I tried to connect to the FileBrowser plugin, I still couldn’t change the Wi-Fi network. I deleted the network.lua and network.lua.old files from the koreader/settings directory to try to “force” a reset of the Wi-Fi connections. So far, I haven’t seen a problem because this behavior was replicated here: #14478

But the problem persisted. I uninstalled the FileBrowser plugin and decided to install FileSync. It ran within the KoReader app, but I was unable to access the files from my computer. I thought I needed to restart the Kindle, so I did. I exited the KoReader app and restarted the Kindle, but when it booted up again, the KoReader app simply wouldn’t open. I tap the home screen to open it, and it just keeps loading indefinitely while “opening.” I don’t know what else to do. Can anyone help me? I jailbroke it over a year ago, but I don’t know the version of either the jailbreak or KoReader. I tried running Run Hotfix Book, but it still isn’t working.

[dandaman]

Try reinstalling KOReader - you will not lose any of your data or settings or plugins in KOReader. Visit scriptlets.notmarek.com, download the "KOReader installer (nightly)" scriptlet, copy it to your Kindle's documents folder via USB.
After you have ejected, tap the new book that appears on your Kindle and try opening KOReader again.
If this still doesn't work, remove the filesync/filebrowserplus plugin folders and try again

[eudesmdcf]

I filed an issue with Koreader support on GitHub, and they advised me to remove the FileSync plugin. After restarting the Kindle, Koreader went back to normal. Thank goodness.