Kobo needs restart almost every time I add books - Page 4

DNSB · 08-17-2026, 04:29 PM

Quote:

Originally Posted by JSWolf

It's still a lot more complicated then epubcheck in the editor. It always will be until epubveri is ready to be made into a plugin and then is.

Odd comment. Open the web page, drag and drop the ePub. Wait a couple of seconds. Not exactly a complicated procedure.

Admittedly, using epubcheck and epubveri as plugins in Sigil is easier especially when you are comparing the error reports.

JSWolf · 08-17-2026, 05:14 PM

I don't have a plugin for epubveri for calibre or sigil. So that makes dealing with error reports more difficult.

Siavahda · 08-24-2026, 01:11 PM

I thought it might be of interest to someone, that the two ebooks I've found so far that cause this problem - neither one had any flaws according to epubcheck. So that doesn't seem to be a very surefire way of identifying these problem books, alas.

PeterT · 08-24-2026, 01:35 PM

If at all possible you might consider sharing these,; either the original if not copy sighted, or a scrambled version if it is

Sent from my SM-X238U using Tapatalk

Siavahda · 08-24-2026, 02:24 PM

Good idea!

They're both copyrighted, so here they are scrambled.

JSWolf · 08-24-2026, 03:27 PM

Quote:

Originally Posted by Siavahda

Good idea!

They're both copyrighted, so here they are scrambled.

Do the scrambled versions cause the problem?

Siavahda · 08-25-2026, 03:24 AM

Quote:

Originally Posted by JSWolf

Do the scrambled versions cause the problem?

I did not think to check that, but now I have: no, the scrambled ones don't cause the problem.

And when I tried adding the unscrambled versions, they didn't either now, even though they definitely did before. (Removing one fixed the problem; adding the other file triggered the problem again, and removing THAT one fixed it for a second time.)

Is it possible it's not the files themselves, it's something going wrong in the process of sending them to the Kobo? Probably on the Kobo side rather than the Calibre side? Or maybe not the sending/adding the file but something like indexing it, some error there.

I tried copy-pasting one of the files into the Kobo rather than sending it via Calibre. That didn't trigger the problem either.

If it's some glitch involved in the process of adding the file to the Kobo, that would explain why both files look perfect to epubcheck. It's random and could happen with ANY ebook file, because it's not the file at all. Maybe???

Siavahda · 08-25-2026, 04:36 AM

It's Tuesday = book release day, and I ran into one of my preorders that caused this problem. It caused the problem both when I used the send-to-device function in Calibre, and also when I copy-pasted the file directly into the Kobo without Calibre.

This file DID upset epubcheck; 912 errors found.

A scrambled version of that file DID cause the problem - not the freezing immediately after disconnecting the Kobo, but freezing after the device goes to sleep for a couple of minutes after it's imported the new book.

Even redownloading the file didn't get me a version that DIDN'T cause the problem.

Sirtel · 08-25-2026, 06:27 AM

Well, I don't know. I have over 2000 books on my Kobos, none of which have ever been checked with epubcheck, and I've never experienced the issue. That's far more books than would be explained just by pure luck. So I'd say there's definitely something here to do with your device or model or firmware.

Siavahda · 08-25-2026, 06:29 AM

Quote:

Originally Posted by Sirtel

Well, I don't know. I have over 2000 books on my Kobos, none of which have ever been checked with epubcheck, and I've never experienced the issue. That's far more books than would be explained just by pure luck. So I'd say there's definitely something here to do with your device or model or firmware.

It does strike me as FAR more likely that the problem is on my end somehow - my device, something I've messed up in Calibre, I don't know. But encountering so many books like this doesn't feel random.

maddz · Yesterday, 02:53 AM

I have a similar problem with one of my Kobos. After sending books, and updating metadata, it freezes on the currently reading screen, and all I can do is wait for the battery to drain before restarting. Pressing the power button for a long time isn't working. Looking at what's on there, I suspect a bunch of data science books I got from Humble Bundle a while back (usually from Pakt). They are all on the large side for epubs (>10 MB). I'll try a factory reset when it's recharged and batch send the books to identify the bad one; the one I've been looking at has over 1850 errors when I run checks in edit books (epubcheck & epubveri installed).

Siavahda · Yesterday, 03:31 AM

Quote:

Originally Posted by maddz

I have a similar problem with one of my Kobos. After sending books, and updating metadata, it freezes on the currently reading screen, and all I can do is wait for the battery to drain before restarting. Pressing the power button for a long time isn't working. Looking at what's on there, I suspect a bunch of data science books I got from Humble Bundle a while back (usually from Pakt). They are all on the large side for epubs (>10 MB). I'll try a factory reset when it's recharged and batch send the books to identify the bad one; the one I've been looking at has over 1850 errors when I run checks in edit books (epubcheck & epubveri installed).

I'm sorry you're having this issue, but thank you for sharing info! The more info we have the better.

Siavahda · Yesterday, 03:34 AM

Yesterday after a lot of scouring forums, I went into my Kobo settings and turned the 'automatically go to sleep after' (under energy savings and privacy) to 'never'. Since then, my Kobo hasn't been freezing as long as I unplug the Kobo from my PC before I close its cover/send it to sleep (instead of leaving it charging). Even with books that a few days ago were definitely making my Kobo freeze!

No idea what's going on, will continue to post updates here.

maddz · Yesterday, 04:54 PM

Wonderful. Did a factory reset on that Kobo, and started transferring books from calibre in batches of 250. Got to a little under half-way, everything transferred and imported successfully. Started on the next set of 250; apparently transferred and uploaded OK, ejected the Kobo, and now it's stuck on the black connected and charging screen. I suppose I'll have to wait for the battery to run flat before I can continue. At least I can then start homing in on the offending book.

PeterT · Yesterday, 05:10 PM

Just unplug the cable. If needs be hold down the power button to force a reboot

Sent from my SM-X238U using Tapatalk

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08-17-2026, 05:14 PM	#47
JSWolf Resident Curmudgeon Posts: 84,651 Karma: 153744859 Join Date: Nov 2006 Location: Roslindale, Massachusetts Device: Kobo Libra 2, Kobo Aura H2O, PRS-650, PRS-T1, nook STR, PW3	I don't have a plugin for epubveri for calibre or sigil. So that makes dealing with error reports more difficult.

08-24-2026, 01:11 PM	#48
Siavahda Addict Posts: 257 Karma: 9400 Join Date: Aug 2010 Location: Helsinki Device: Kobo Clara Colour	I thought it might be of interest to someone, that the two ebooks I've found so far that cause this problem - neither one had any flaws according to epubcheck. So that doesn't seem to be a very surefire way of identifying these problem books, alas.

08-24-2026, 01:35 PM	#49
PeterT Grand Sorcerer Posts: 14,077 Karma: 83386418 Join Date: Nov 2007 Location: Toronto Device: Libra H2O, Libra Colour	If at all possible you might consider sharing these,; either the original if not copy sighted, or a scrambled version if it is Sent from my SM-X238U using Tapatalk

08-25-2026, 04:36 AM	#53
Siavahda Addict Posts: 257 Karma: 9400 Join Date: Aug 2010 Location: Helsinki Device: Kobo Clara Colour	It's Tuesday = book release day, and I ran into one of my preorders that caused this problem. It caused the problem both when I used the send-to-device function in Calibre, and also when I copy-pasted the file directly into the Kobo without Calibre. This file DID upset epubcheck; 912 errors found. A scrambled version of that file DID cause the problem - not the freezing immediately after disconnecting the Kobo, but freezing after the device goes to sleep for a couple of minutes after it's imported the new book. Even redownloading the file didn't get me a version that DIDN'T cause the problem.

08-25-2026, 06:27 AM	#54
Sirtel Grand Sorcerer Posts: 15,614 Karma: 249250117 Join Date: Jan 2014 Location: Estonia Device: Kobo Sage & Libra 2	Well, I don't know. I have over 2000 books on my Kobos, none of which have ever been checked with epubcheck, and I've never experienced the issue. That's far more books than would be explained just by pure luck. So I'd say there's definitely something here to do with your device or model or firmware.

Yesterday, 02:53 AM	#56
maddz Wizard Posts: 1,593 Karma: 30468958 Join Date: Mar 2010 Location: UK Device: Kobo Forma, Icarus, iPad Mini 2, Kobo Touch, Google Nexus 7	I have a similar problem with one of my Kobos. After sending books, and updating metadata, it freezes on the currently reading screen, and all I can do is wait for the battery to drain before restarting. Pressing the power button for a long time isn't working. Looking at what's on there, I suspect a bunch of data science books I got from Humble Bundle a while back (usually from Pakt). They are all on the large side for epubs (>10 MB). I'll try a factory reset when it's recharged and batch send the books to identify the bad one; the one I've been looking at has over 1850 errors when I run checks in edit books (epubcheck & epubveri installed).

Yesterday, 03:34 AM	#58
Siavahda Addict Posts: 257 Karma: 9400 Join Date: Aug 2010 Location: Helsinki Device: Kobo Clara Colour	Yesterday after a lot of scouring forums, I went into my Kobo settings and turned the 'automatically go to sleep after' (under energy savings and privacy) to 'never'. Since then, my Kobo hasn't been freezing as long as I unplug the Kobo from my PC before I close its cover/send it to sleep (instead of leaving it charging). Even with books that a few days ago were definitely making my Kobo freeze! No idea what's going on, will continue to post updates here.

Yesterday, 04:54 PM	#59
maddz Wizard Posts: 1,593 Karma: 30468958 Join Date: Mar 2010 Location: UK Device: Kobo Forma, Icarus, iPad Mini 2, Kobo Touch, Google Nexus 7	Wonderful. Did a factory reset on that Kobo, and started transferring books from calibre in batches of 250. Got to a little under half-way, everything transferred and imported successfully. Started on the next set of 250; apparently transferred and uploaded OK, ejected the Kobo, and now it's stuck on the black connected and charging screen. I suppose I'll have to wait for the battery to run flat before I can continue. At least I can then start homing in on the offending book.

Yesterday, 05:10 PM	#60
PeterT Grand Sorcerer Posts: 14,077 Karma: 83386418 Join Date: Nov 2007 Location: Toronto Device: Libra H2O, Libra Colour	Just unplug the cable. If needs be hold down the power button to force a reboot Sent from my SM-X238U using Tapatalk