KOReader makes my Kobo Clara BW reboot

[Thrill]

Hi everyone

Today I bought a Kobo Clara BW for my wife and tried to install KOReader, but I have a problem.

I followed this video guide on Windows:
https://youtu.be/rEouRrPKj-c

KOReader installs fine and I can see it in NickelMenu. But when I press KOReader, it starts to load and then the device reboots. This happens every time I try to open KOReader.

I followed this guide:
https://www.mobileread.com/forums/sh...96&postcount=2
And I installed KOReader from here:
https://www.mobileread.com/forums/sh...d.php?t=314220

No matter what I do, it always reboots when I try to start KOReader on my Kobo Clara BW.

I’m very new to all of this, so maybe I’m missing something simple. What am I doing wrong? Any help would be really appreciated.

[DNSB]

Posting multiple copies of the same message is not permitted. I've removed your post from the OCP thread in the Kobo Developer's forum and moved my reply here.

If you look in the .adds/nm directory on your Kobo, do you see a file called koreader? If so, edit it to remove all but the last 2 lines and remove the # from the start of the last line. The original file should look like the first sample below and the modified file should look like the second sample below:

# Launch KOReader via KFMon
# NOTE: .adds/nm/kfmon will generate this automatically
#menu_item : main : KOReader : kfmon     : koreader.png

# Launch KOReader directly via NM (>= KOReader 2020.05)
#menu_item : main : KOReader : cmd_spawn : quiet : exec /mnt/onboard/.adds/koreader/koreader.sh

# Launch KOReader directly via NM (>= KOReader 2020.05)
menu_item : main : KOReader : cmd_spawn : quiet : exec /mnt/onboard/.adds/koreader/koreader.sh

This will launch KOReader directly from the .sh file instead of detouring through KFMon. If this works, it suggests a firmware update has munged KFMon.

If this doesn't work, you might want to try updating KOReader to the latest nightly release since your Kobo BW has probably updated to firmware 4.42.23296 and this may be causing issues. You can find the KOReader nightly releases at https://build.koreader.rocks/download/nightly/ and the current as of today Kobo release at koreader-kobo-v2025.04-121-g4dc4339bc_2025-06-14.zip

Once you have the nightly file downloaded, unpack it and copy the koreader directory into the .adds directory on your Kobo.

Good luck!

[Thrill]

Originally Posted by DNSB

Posting multiple copies of the same message is not permitted. I've removed your post from the OCP thread in the Kobo Developer's forum and moved my reply here.

If you look in the .adds/nm directory on your Kobo, do you see a file called koreader? If so, edit it to remove all but the last 2 lines and remove the # from the start of the last line. The original file should look like the first sample below and the modified file should look like the second sample below:

# Launch KOReader via KFMon
# NOTE: .adds/nm/kfmon will generate this automatically
#menu_item : main : KOReader : kfmon     : koreader.png

# Launch KOReader directly via NM (>= KOReader 2020.05)
#menu_item : main : KOReader : cmd_spawn : quiet : exec /mnt/onboard/.adds/koreader/koreader.sh

# Launch KOReader directly via NM (>= KOReader 2020.05)
menu_item : main : KOReader : cmd_spawn : quiet : exec /mnt/onboard/.adds/koreader/koreader.sh

This will launch KOReader directly from the .sh file instead of detouring through KFMon. If this works, it suggests a firmware update has munged KFMon.

If this doesn't work, you might want to try updating KOReader to the latest nightly release since your Kobo BW has probably updated to firmware 4.42.23296 and this may be causing issues. You can find the KOReader nightly releases at https://build.koreader.rocks/download/nightly/ and the current as of today Kobo release at koreader-kobo-v2025.04-121-g4dc4339bc_2025-06-14.zip

Once you have the nightly file downloaded, unpack it and copy the koreader directory into the .adds directory on your Kobo.

Good luck!

Will give it a go, whatsoever I believe the issue is deeper than I thought. I did find this issue in the koreader git: https://github.com/koreader/koreader/issues/13644 and it looks like it is a bug and we might need wait for it to be fixed

[DNSB]

Originally Posted by Thrill

Will give it a go, whatsoever I believe the issue is deeper than I thought. I did find this issue in the koreader git: https://github.com/koreader/koreader/issues/13644 and it looks like it is a bug and we might need wait for it to be fixed

I saw that one back in April but hadn't realized that it wasn't fully implemented yet.