a strange error

[DragoLord19d]

I'm getting a weird error when trying to open my epubs

calibre, version 9.9.0
ERROR: Loading book failed: Failed to open the book at C:\Users\Owner\OneDrive\Documents\Calibre\Silver Gambit\With Key in Hand (3037)\With Key in Hand - Silver Gambit.epub. Click "Show details" for more info.

Failed to convert book: C:\Users\Owner\OneDrive\Documents\Calibre\Silver Gambit\With Key in Hand (3037)\With Key in Hand - Silver Gambit.epub with error:
calibre_plugins.comicvine.utils:228: SyntaxWarning: "\d" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\d"? A raw string is also an option.
calibre_plugins.comicvine.utils:228: SyntaxWarning: "\g" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\g"? A raw string is also an option.
calibre_plugins.comicvine.utils:234: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.fantastic_fiction.__init__:96: SyntaxWarning: "\." is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\."? A raw string is also an option.
calibre_plugins.fantastic_fiction_adults.__init__: 128: SyntaxWarning: "\." is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\."? A raw string is also an option.

[gbm]

here is your problem:

Loading book failed: Failed to open the book at C:\Users\Owner\OneDrive\Documents\Calibre\Silver Gambit\With Key in Hand (3037)\With Key in Hand - Silver Gambit.epub.

https://manual.calibre-ebook.com/faq...rked-drive-nas

See for help:
https://www.mobileread.com/forums/sh...54&postcount=4

luck

bernie

Originally Posted by DragoLord19d

I'm getting a weird error when trying to open my epubs

calibre, version 9.9.0
ERROR: Loading book failed: Failed to open the book at C:\Users\Owner\OneDrive\Documents\Calibre\Silver Gambit\With Key in Hand (3037)\With Key in Hand - Silver Gambit.epub. Click "Show details" for more info.

Failed to convert book: C:\Users\Owner\OneDrive\Documents\Calibre\Silver Gambit\With Key in Hand (3037)\With Key in Hand - Silver Gambit.epub with error:
calibre_plugins.comicvine.utils:228: SyntaxWarning: "\d" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\d"? A raw string is also an option.
calibre_plugins.comicvine.utils:228: SyntaxWarning: "\g" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\g"? A raw string is also an option.
calibre_plugins.comicvine.utils:234: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.fantastic_fiction.__init__:96: SyntaxWarning: "\." is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\."? A raw string is also an option.
calibre_plugins.fantastic_fiction_adults.__init__: 128: SyntaxWarning: "\." is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\."? A raw string is also an option.

[JSWolf]

Get your calibre library out of the path of Onedrive.

[lyfia]

Originally Posted by gbm

here is your problem:

Loading book failed: Failed to open the book at C:\Users\Owner\OneDrive\Documents\Calibre\Silver Gambit\With Key in Hand (3037)\With Key in Hand - Silver Gambit.epub.

https://manual.calibre-ebook.com/faq...rked-drive-nas

See for help:
https://www.mobileread.com/forums/sh...54&postcount=4

luck

bernie

I have the same bug even outside network drives:

calibre, version 9.9.0
calibre, version 9.9.0
ERROR: Loading book failed: Failed to open the book at D:\Downloads\A Life - Oxford University Press.epub. Click "Show details" for more info.

Failed to convert book: D:\Downloads\A Life - Oxford University Press.epub with error:

Originally the bug is exactly the same as in OP (same "comicvine", same problems with escape slashes), so I uninstalled the comicvine plugin , then the error message became blank --- what I pasted above. I've tried restarting calibre and Windows.

[kovidgoyal]

That error indicates something on your machine is killing calibre worker processes, reboot in safe mode and see if it works.

[lyfia]

Originally Posted by kovidgoyal

That error indicates something on your machine is killing calibre worker processes, reboot in safe mode and see if it works.

I'd try but my computer crashes at any attempt to reboot into safe mode. That'll be another one for me to debug.

But I don't think it's caused by disrupted calibre worker processes because I can right-click and open other EPUBs within the same E-book viewer window, showing the same number of calibre worker processes in Task Manager when it succeeded or failed. I can't tell why some EPUBs work while others don't, but I know for a fact the failed EPUBs were still working two weeks ago. They are not corrupted files, and they can still be opened in other programs, including the calibre ebook editor (which didn't find notable errors with these files, by the way).

[gbm]

Advice back up your libraries and config folder then run smart drive on your disk.

https://www.elevenforum.com/t/check-drive-health-and-smart-status-in-windows-11.8778/
If it passes smart drive then:

https://www.elevenforum.com/t/check-...ndows-11.8046/

bernie

bernie

Originally Posted by lyfia

I'd try but my computer crashes at any attempt to reboot into safe mode. That'll be another one for me to debug.

But I don't think it's caused by disrupted calibre worker processes because I can right-click and open other EPUBs within the same E-book viewer window, showing the same number of calibre worker processes in Task Manager when it succeeded or failed. I can't tell why some EPUBs work while others don't, but I know for a fact the failed EPUBs were still working two weeks ago. They are not corrupted files, and they can still be opened in other programs, including the calibre ebook editor (which didn't find notable errors with these files, by the way).

[lyfia]

Thanks bernie, my disks passed all the checks. Other programs can open those EPUBs, so they are not corrupted. As for the crashes, I've recently upgraded my PC so it may be a driver issue, otherwise I suspect Windows update KB5094126.

[DiapDealer]

Originally Posted by kovidgoyal

That error indicates something on your machine is killing calibre worker processes, reboot in safe mode and see if it works.

Originally Posted by lyfia

I'd try but my computer crashes at any attempt to reboot into safe mode. That'll be another one for me to debug.

Originally Posted by JSWolf

I suggest you try rebooting in safe mode and then try calibre.

Why would you think they need instructions on how to boot to Safe Mode when they clearly already indicated their computer crashes whenever trying to reboot into Safe Mode?

[JSWolf]

@lyfia what you need to di is a repair install. It's the only way to fix your computer without a full reinstall.

Go to Settings > System > Recovery > Fix Problems using Windows Update

[lyfia]

Thanks for the help but actually I've already done that. I've also ruled out recent Windows updates. It seems I'll have to do a full reinstall/reset to fix the drivers, but it's a bit off-topic.

Attached are 3 books that I've read in the past 2 months without problems with the calibre reader. I've even highlighted and taken notes. Only the Japanese book ("kimi no suizou") still works now. Perhaps you can tell the difference between what works and what doesn't.

[lyfia]

Originally Posted by lyfia

Only the Japanese book ("kimi no suizou") still works now.

WAIT NO. The file I uploaded actually does not work. Strange but finally some development.

The original file still works (uploaded below). I copied it to another folder and renamed it (because the original has an ugly transliterated filename) for upload, the one I uploaded in the previous post, and now it can't be opened!!

[lyfia]

Guys I found the issue!! After disabling the plugin "ePub Extended Metadata {Reader}" everything's back to normal. The problematic plugin update is its latest on 2026-06-21.
Weird that calibre's Traceback couldn't catch this, though.

[un_pogaz]

So, their is a very odd bug that when I use my automated process to ZIP the files of "ePub Extended Metadata", Calibre is some how unable to read it.
https://www.mobileread.com/forums/sh...3&postcount=55

I need to no manual shenigany to solve it.

And the most odd non-sens: Not all book trigger the bug.

[un_pogaz]

After more investigation, I cannot longuer product valid ZIP file (without the bug), even manualy, and it clear it a top level calibre issue or related.

calibre, version 9.10.0
ERREUR : Impossible d'ajouter les livres: Échec lors de l'ajout de certains livres, cliquez sur "Afficher les détails" pour plus d'information.

Worker process crashed while executing job
Traceback (most recent call last):
  File "calibre/utils/ipc/pool.py", line 106, in recv
  File "calibre/utils/ipc/__init__.py", line 20, in eintr_retry_call
  File "multiprocessing/connection.py", line 226, in recv_bytes
  File "multiprocessing/connection.py", line 451, in _recv_bytes
  File "multiprocessing/connection.py", line 420, in _recv
EOFError

Inside my plugin, the exact line that raise the error is the following:
reader/__init__.py:40

37|        if find_plugin(self.name):
38|            if hasattr(stream, 'seek'):
39|                stream.seek(0)
40|            from ..action import read_metadata
41|            return read_metadata(stream, type, mi)
42|        else:
43|            return mi

Their is no reason that this import fail. Really I looked it hard.

Plugin source code is on GitHub.