Troubleshooting Kindle 4 can't launch KUAL after getting out of KOReader.

Brandacafe · 04-17-2025, 12:23 PM

Hello everyone!

I've recently got a Kindle 4 and wanted to jailbreak it. After doing everything step by step it worked and I installed KUAL and KOReader, everything worked perfectly but when I exited KOReader and wanted to launch KUAL and get back into KOReader I was met with this error: "The permissions to open this item have expired. Please contact the developer."

I tried a few other times but same error appeared so I factory restored the Kindle and upgraded to FW 4.1.4. (It was on 4.1.3) and do the jailbreak again. But the same error appeared and it didn't even work the first time as it did before.

I'd really like to use the Kindle as it's in great shape, can someone help me?

Thank you so much to everyone in advance!

Ebookus · 04-17-2025, 06:18 PM

yeah, this appears to be a thing now. I am facing the same on k3 and other people have reported similar issues as well. It seems, the best course of action is to avoid leaving koreader if you have an old (ish) device until someone figures out what is going out. as for those of us unable to launch kual... we'll have to wait and see

skearth · 04-17-2025, 08:47 PM

My partner and I both have Kindle 4's (K4) and are having the same exact issue with KUAL and it started today, I have nothing to add just wanting to note that neither of us can find a fix

roger64 · 04-18-2025, 04:06 AM

Same problem about KUAL (already reported on topic koreader) and same day for my PW3...

tangents · 04-18-2025, 06:54 AM

just wanted to add that i also have a K4 and am dealing with this issue; it worked perfectly yesterday.

shamanNS · 04-18-2025, 07:06 AM

It worked and now it doesn't because the "developer.keystore" used by KUAL expired yesterday morning.

Until KUAL gets a new release the only way to keep using the old/existing one would be to intentionally set the date/time on your Kindle to wrong date that's XY days in the past, so you fool the device in thinking that certificate is still valid.

https://www.mobileread.com/forums/sh...7&postcount=13

Ebookus · 04-18-2025, 08:38 AM

Quote:

Originally Posted by shamanNS

It worked and now it doesn't because the "developer.keystore" used by KUAL expired yesterday morning.

Until KUAL gets a new release the only way to keep using the old/existing one would be to intentionally set the date/time on your Kindle to wrong date that's XY days in the past, so you fool the device in thinking that certificate is still valid.

https://www.mobileread.com/forums/sh...7&postcount=13

shoot. is that something that anyone in the community can do or... something that only a maintainer can do?

roger64 · 04-18-2025, 10:49 AM

I had a PW3 wifi running 5.7.4. It had been jailbroken years ago and koreader was working.

I tried winterbreak on it but failed (stuck at "wait" after reporting jailbreak done).
I managed to update manually Kindle to 5.14.1. Kindle is going strongly now.
I shall try again winterbreak, and if I succeed , I hope that the new Kual install will be immune to this problem. If one developer could confirm this point, it would be nice. I'll try again the jailbreak after the week-end.

The main difficulty seems to be not allowing OTA updates during the install of the jailbreak. Steps have to be carefully calculated.

Ebookus · 04-18-2025, 11:13 AM

Quote:

Originally Posted by roger64

I had a PW3 wifi running 5.7.4. It had been jailbroken years ago and koreader was working.

I tried winterbreak on it but failed (stuck at "wait" after reporting jailbreak done).
I managed to update manually Kindle to 5.14.1. Kindle is going strongly now.
I shall try again winterbreak, and if I succeed , I hope that the new Kual install will be immune to this problem. If one developer could confirm this point, it would be nice. I'll try again the jailbreak after the week-end.

The main difficulty seems to be not allowing OTA updates during the install of the jailbreak. Steps have to be carefully calculated.

Wrong thread perhaps?

Brandacafe · 04-18-2025, 12:51 PM

We'll have to wait then, thanks for the info!

roger64 · 04-21-2025, 05:46 AM

The problem in this thread is that Kual had stopped working. This happened the same day for my PW3 as for Brandacafe. I used Kual to start Koreader. I got it working again.

This is what I did, if somebody has a better way, so be it.

- updating manually my Kindle from 5.7.4 (8 years ago...) to 5.14.2

According to your machine, there are several update.bin packages available listed in the menu of Winterbreak (see firmware and flashing).

- then I applied very carefully the Winterbreak procedure. The new install of Kual is one of the many steps you'll have to follow.

I did not reinstall koreader which was already on my machine. I just copied the helper and koreader folders which were in my old extensions folder to the new extensions folder. Then I rebooted. Kual can start again koreader. I could also update my current version of koreader which was one year old.

One expert on the koreader forum gave another and much shorter solution that I did not have the opportunity to try. Up to you...
https://www.mobileread.com/forums/sh...13&postcount=3

Brandacafe · 04-25-2025, 02:21 PM

I have been trying lots of things, I updated the Devkeys to the new ones and now I'm getting this error always:

"An error occured:Main class instantiation threw a RuntimeException. Please contact the developer."

I have tried fresh jailbreaks, checked the threads with the same error but I can't seem to fix it. Some say waiting about 30 seconds after first error should work but no matter how many times I try it just outputs the same error.

I have factory restored and will try anything you guys tell me from scratch.

Thanks for the help!

04-17-2025, 12:23 PM	#1
Brandacafe Junior Member Posts: 3 Karma: 10 Join Date: Apr 2025 Device: Kindle 4	Kindle 4 can't launch KUAL after getting out of KOReader. Hello everyone! I've recently got a Kindle 4 and wanted to jailbreak it. After doing everything step by step it worked and I installed KUAL and KOReader, everything worked perfectly but when I exited KOReader and wanted to launch KUAL and get back into KOReader I was met with this error: "The permissions to open this item have expired. Please contact the developer." I tried a few other times but same error appeared so I factory restored the Kindle and upgraded to FW 4.1.4. (It was on 4.1.3) and do the jailbreak again. But the same error appeared and it didn't even work the first time as it did before. I'd really like to use the Kindle as it's in great shape, can someone help me? Thank you so much to everyone in advance!

04-18-2025, 07:06 AM	#6
shamanNS Wizard Posts: 1,091 Karma: 12000090 Join Date: Feb 2010 Location: Serbia Device: Kindle PW5, Kobo Libra 2, Kindle PW1	It worked and now it doesn't because the "developer.keystore" used by KUAL expired yesterday morning. Until KUAL gets a new release the only way to keep using the old/existing one would be to intentionally set the date/time on your Kindle to wrong date that's XY days in the past, so you fool the device in thinking that certificate is still valid. https://www.mobileread.com/forums/sh...7&postcount=13 Last edited by shamanNS; 04-18-2025 at 07:12 AM.

04-18-2025, 10:49 AM	#8
roger64 Wizard Posts: 2,623 Karma: 3000161 Join Date: Jan 2009 Device: Kindle PW3 (wifi)	I had a PW3 wifi running 5.7.4. It had been jailbroken years ago and koreader was working. I tried winterbreak on it but failed (stuck at "wait" after reporting jailbreak done). I managed to update manually Kindle to 5.14.1. Kindle is going strongly now. I shall try again winterbreak, and if I succeed , I hope that the new Kual install will be immune to this problem. If one developer could confirm this point, it would be nice. I'll try again the jailbreak after the week-end. The main difficulty seems to be not allowing OTA updates during the install of the jailbreak. Steps have to be carefully calculated. Last edited by roger64; 04-18-2025 at 10:54 AM.

04-21-2025, 05:46 AM	#11
roger64 Wizard Posts: 2,623 Karma: 3000161 Join Date: Jan 2009 Device: Kindle PW3 (wifi)	The problem in this thread is that Kual had stopped working. This happened the same day for my PW3 as for Brandacafe. I used Kual to start Koreader. I got it working again. This is what I did, if somebody has a better way, so be it. - updating manually my Kindle from 5.7.4 (8 years ago...) to 5.14.2 According to your machine, there are several update.bin packages available listed in the menu of Winterbreak (see firmware and flashing). - then I applied very carefully the Winterbreak procedure. The new install of Kual is one of the many steps you'll have to follow. I did not reinstall koreader which was already on my machine. I just copied the helper and koreader folders which were in my old extensions folder to the new extensions folder. Then I rebooted. Kual can start again koreader. I could also update my current version of koreader which was one year old. One expert on the koreader forum gave another and much shorter solution that I did not have the opportunity to try. Up to you... https://www.mobileread.com/forums/sh...13&postcount=3 Last edited by roger64; 04-21-2025 at 06:36 AM.

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04-17-2025, 06:18 PM	#2
Ebookus Digital Grenadier Posts: 162 Karma: 1500000 Join Date: Jan 2024 Device: Kindle	yeah, this appears to be a thing now. I am facing the same on k3 and other people have reported similar issues as well. It seems, the best course of action is to avoid leaving koreader if you have an old (ish) device until someone figures out what is going out. as for those of us unable to launch kual... we'll have to wait and see

04-17-2025, 08:47 PM	#3
skearth Junior Member Posts: 1 Karma: 10 Join Date: Apr 2025 Device: K4	My partner and I both have Kindle 4's (K4) and are having the same exact issue with KUAL and it started today, I have nothing to add just wanting to note that neither of us can find a fix

04-18-2025, 04:06 AM	#4
roger64 Wizard Posts: 2,623 Karma: 3000161 Join Date: Jan 2009 Device: Kindle PW3 (wifi)	Same problem about KUAL (already reported on topic koreader) and same day for my PW3...

04-18-2025, 06:54 AM	#5
tangents Junior Member Posts: 1 Karma: 10 Join Date: Apr 2025 Device: K4	just wanted to add that i also have a K4 and am dealing with this issue; it worked perfectly yesterday.

04-18-2025, 12:51 PM	#10
Brandacafe Junior Member Posts: 3 Karma: 10 Join Date: Apr 2025 Device: Kindle 4	We'll have to wait then, thanks for the info!

04-25-2025, 02:21 PM	#12
Brandacafe Junior Member Posts: 3 Karma: 10 Join Date: Apr 2025 Device: Kindle 4	I have been trying lots of things, I updated the Devkeys to the new ones and now I'm getting this error always: "An error occured:Main class instantiation threw a RuntimeException. Please contact the developer." I have tried fresh jailbreaks, checked the threads with the same error but I can't seem to fix it. Some say waiting about 30 seconds after first error should work but no matter how many times I try it just outputs the same error. I have factory restored and will try anything you guys tell me from scratch. Thanks for the help!

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