Tools Snapshots of NiLuJe's hacks

[zooterkin]

Originally Posted by famewolf

You need to install the MKK package which updates the signatures so the package is authorized. See the first post.

I've done that, but still get the error when I try to open the KUAL document. Tried various solutions presented here, but it's hard to know what's still relevant.

I've got a Kindle Keyboard 3.

It looks to me as though the current set of archives need to be updated as something has timed out. Is this planned?

I'm probably not going to spend any more time on getting KUAL working, as I suspect it doesn't add much for me. I got launchpad and KOReader working, and will probably look at Calibre integration and USBNetwork next.

[rafikius]

Originally Posted by chaitanyaI

for all who have issue that "The title is not signed by a registered developer"
I found a temporary solution until developers pitch in to correct the issue.
This is the only solution that worked for me on KPW1 after 3 days and multiple resets. Upgrade to 5.6.1.1 finally after everything worked for me.

Brother!

Your advice saved me from turning gray haired too early!
it was updating firmware to 5.6.1.1 that solved the issue of the "signature" error.

as of 15 of June 2026 I confirm the above described methodic has allowed me to lunch Kual and install KOReader on my PW1 with 5.4.4 firmware.

[thewoz]

so this is the holy grail of the kindle jailbreaking, its nice to be here! I am developing apps for my kual more specifically a habit tracker.

[kokoko]

Are the certs expired again?

I am trying to install Koreader. The common path is

• jailbreak (done - Update_jailbreak_k3w_install.bin)
• mkk (done - Update_mkk-20141129-k3w-B008_install.bin + Update-mkk-20250419-k3w-B008_keystore-install)
• kual (stuck here - KUAL-KDK-1.0.azw2)
• koreader (not tried)

The issue with running KUAL is "The title is not signed by a registered developer.".

I have found the thread that everyone mentions - https://www.mobileread.com/forums/sh...postcount=1295 - and installed the "Update-mkk-20250419-k3w-B008_keystore-install.bin" which should have uppdated the keystore - but it still doesn't work. I even tried to copy the new KUAL (KUAL-KDK-1.0.azw2) to the reader again (just to be sure) and I am still getting the infamous error.

I also tried to set date to past, but it i wasn't successful (Seems that this kindle (3, firmware 3.4) doesn't really support it directly (only time can be changed) - I also tried to set it through ;debugOn, date "commands" but it did not work).

[Frogm4n]

Did you leave the wifi on? That will break the MKK certs until you block it from talking to Amazon servers.

[kokoko]

Originally Posted by Frogm4n

Did you leave the wifi on? That will break the MKK certs until you block it from talking to Amazon servers.

No, the Wi-Fi was off the whole time, but thank you for the tip.

I made it work eventually - but I'm not sure what helped (posting here as it might help others):

• factory reset
• i updated from firmware 3.4 to 3.4.2 and then to 3.4.3 (latest there is for this Kindle)
• (few rounds of installing jailbreak, mkk, mkk update, kual, -> error, factory reset..)
• then in one round i actually did NOT install the mkk update that is supposed to fix the KUAL issue, just the original MKK (I wasn't sure this would help, i just tried to run KUAL without the update and...voila, it worked)

[Frogm4n]

Originally Posted by kokoko

[*]i updated from firmware 3.4 to 3.4.2 and then to 3.4.3 (latest there is for this Kindle)

This was the fix. The 2025 Dev Certs need to be installed on the latest firmware each device runs.

[whiskeyfoxtrot]

Hi! I'm stuck on this too - trying to set up my ancient kindle to be used as a little display.

Kindle 3 WiFi (B008), FW 3.4.3, purchased pre-Special-Offers era.

Sequence: factory reset → jailbreak 0.13.N (k3w) succeeded clean → MKK 20141129 (k3w-B008) succeeded clean, developer + linkjail folders present → KUALBooklet v2.7.37 and KUAL-KDK-1.0.azw2 both fail: KUALBooklet gives U002 on "Update Your Kindle," KUAL-KDK-1.0 opens with "This title is not signed by a registered developer."

Tried official firmware reflash (Update_2687240004-3543620001.bin) hoping to replicate the fix in post #1476 — but "Update Your Kindle" is grayed out since I'm already on 3.4.3 from the factory reset, so there's no version step to climb like kokoko did.

Any ideas what's different about my case, or what else to check? Elbow grease in this forum + Claude + asking my Kindle nicely has gotten me this far but I am so stuck

[hango]

Hi guys, I followed the installation of the screensavers hack. I added a single png into the linkss/screensavers folder and did a framework restart. Now it is stuck at restart screen with text "S checking screensavers...". Please help.

Device PW3

[anon235234625243]

Originally Posted by whiskeyfoxtrot

Hi! I'm stuck on this too - trying to set up my ancient kindle to be used as a little display.

Kindle 3 WiFi (B008), FW 3.4.3, purchased pre-Special-Offers era.

Sequence: factory reset → jailbreak 0.13.N (k3w) succeeded clean → MKK 20141129 (k3w-B008) succeeded clean, developer + linkjail folders present → KUALBooklet v2.7.37 and KUAL-KDK-1.0.azw2 both fail: KUALBooklet gives U002 on "Update Your Kindle," KUAL-KDK-1.0 opens with "This title is not signed by a registered developer."

Tried official firmware reflash (Update_2687240004-3543620001.bin) hoping to replicate the fix in post #1476 — but "Update Your Kindle" is grayed out since I'm already on 3.4.3 from the factory reset, so there's no version step to climb like kokoko did.



Any ideas what's different about my case, or what else to check? Elbow grease in this forum + Claude + asking my Kindle nicely has gotten me this far but I am so stuck

Hi i have this exact issue on the K2i with firmwate 2.5.8 did you find a fix for this? it would really help if you did!

[thevetev]

hey. stuck on something and could use a sanity check before i touch this thing again.

device is a Kindle Keyboard 3G, serial starts B00A, so the Europe variant, k3gb. firmware
is 3.4.3, confirmed on the Settings screen. it's un-jailbroken right now.


background

this Kindle was jailbroken in november 2010. it still had NiLuJe's ScreenSavers hack
0.18.N on it, and linkss/backups/prettyversion.txt said "Kindle 3.1". that jailbreak
survived every OTA up to 3.4.2 and was still running, a fresh
linkss/run/usb-watchdog.pid was getting written on every USB connect.

i wanted USBNetwork for ssh. that's where it went wrong.


what i did, in order

all of these via Settings > Menu > Update Your Kindle, file at the volume root, ejected
and unplugged first, wireless off the whole time.

1. Update_usbnetwork_0.57.N_k2_dx_k3_install.bin
FAILED, generic "not successful", no error code.
found the cause later: USBNetwork 0.57.N needs jailbreak >= 0.11.N (its
README.txt:98) and mine was from 2010.

2. Update_jailbreak_0.13.N_k3gb_uninstall.bin
SUCCESS.

3. Update_jailbreak_0.13.N_k3gb_install.bin
FAILED, generic, no code.

4. same file, after a full Restart
FAILED.

5. same file, after Restart plus renaming /mnt/us/linkss to disable the 2010 hack
(checked it wasn't running: stale PID file, no mounted_* marker created)
FAILED.

6. Update_usbnetwork_0.57.N_k2_dx_k3_install.bin again
FAILED, which confirms 3 to 5 never took.

7. firmware 3.4.2 to 3.4.3, official Amazon B00A file
SUCCESS.

8. Update_jailbreak_0.13.N_k3gb_install.bin on 3.4.3
FAILED, generic, no code.

step 2 was because README.txt:31 says updating the jailbreak on a 3.x device is one of
the cases where you run the uninstaller first, and the v0.9.N changelog says the
installer aborts if another jailbreak is there. in hindsight that was the mistake.

step 7 was on the back of two threads saying 3.4.3 is needed for 0.13.N to install
(t=372804, and a confirmed success on 3.4.3 in t=352993). didn't help.


stuff i already checked, so you don't have to ask

correct variant. README.txt:65 says "k3gb means K3 3G (UK [B00A])". my serial starts
B00A. i used k3gb, not k3g.

correct variant again, checked at the byte level. the OTA header is FC02 and the device
id at offset 0x0C is different across the three K3 packages, exactly like you'd expect:

Update_jailbreak_0.13.N_k3g_install.bin 06 00 00 00 B006
Update_jailbreak_0.13.N_k3w_install.bin 08 00 00 00 B008
Update_jailbreak_0.13.N_k3gb_install.bin 0a 00 00 00 B00A <- mine

correct FW variant. i didn't use the -3.0-to-3.2 file, the README says those are for FW
3.2 and below only.

file integrity. archive kindle-jailbreak-0.13.N-r18833.tar.xz md5
a5605097853b97dbc0aba09df611d5e0, matches the Snapshots listing. the extracted
Update_jailbreak_0.13.N_k3gb_install.bin is md5 6f98c96fe96cbbb63eb7784ecbbbbcf2,
260 KB. i re-checked the copy sitting on the Kindle root byte for byte before the last
attempt.

correct procedure. file at the volume root, ejected and unplugged, then
[HOME] > [MENU] > Settings > [MENU] > Update Your Kindle. never rebooted with a .bin
sitting at the root.

the updater itself works. steps 2 and 7 both succeeded, so it's not a broken update
path, a bad cable, or a transfer problem.

wireless off, airplane mode, for every attempt.

no error code, ever. t=372804 reports U007 / U004 / Error 3, i only ever get "not
successful". no U006, and never "Another Jailbreak found".


what i think is actually wrong

i ran the 2023 uninstaller against a 2010 jailbreak. the ScreenSavers hack's own
info.txt warns "if you wish to uninstall me, you'll at least need the uninstaller from
that version", and i suspect the same goes for the jailbreak. so the device is probably
half-uninstalled now, not jailbroken but not cleanly stock either.

what makes me think that: the 2010 hack's system side hook kept running after the
uninstall reported success. linkss/run/usb-watchdog.pid was still being refreshed on
every USB connect afterwards. something survived on the system partition.


one thing from the package source

reading src/build-updates.sh, the install bins pack 3.1-install.sh into the OTA tarball
under deliberately mangled filenames ("updatedat", "update\dat", "3.2.1-jb.sig"). so the
exploit looks like signature filename resolution trickery rather than anything that
depends on a pre-installed key. if i'm reading that right, a genuinely stock device
should still be jailbreakable, which is why i don't think i've locked myself out for
good. would like that confirmed though.


questions

1. does a half-removed jailbreak match this silent, no-error-code failure?

2. any way to fully clean /etc/uks/, /etc/init.d/jailbreak, /etc/rc5.d/S64jailbreak and
/etc/rc3.d/K09jailbreak without shell access? bit of a chicken and egg, shell access
is what i was trying to get.

3. is 0.13.N supposed to install on a genuinely stock, never-jailbroken K3 at 3.4.3?
there's a 2026 step by step guide going around that says yes, and its author did
exactly that.

4. would a factory reset clear the remnants, or make it worse?

5. should i try the k3g file instead of k3gb, given USBNetwork ships a single k2_dx_k3
package for all K3 variants? or is that a bad idea on a B00A?

6. any other route for a K3 at 3.4.3, LanguageBreak, WatchThis, KindleBreak?

device is otherwise fine and all the content is backed up. happy to run diagnostics, i
just have no shell, which is the whole problem.

thanks. and thanks for a jailbreak that quietly survived fifteen years of OTAs.