Calibre has suddenly stopped opening my ebooks.

[Innula]

For no apparent reason -- I'd not done anything that might obviously have affected Calibre -- yesterday I found I couldn't open any ebooks on my PC, though I had been reading them earlier in the day.

I've tried uninstalling and reinstalling several different versions of Calibre to see if that helps, and also temporarily disabling my anti-virus, Emisoft (which I'd seen suggested in another thread). Didn't help.

The ebook reader opens, slowly, tries to load the book and then fails with the following message

calibre, version 2.55.0
ERROR: Could not open ebook: Failed to read book, C:\Users\Home\Google Drive\Calibre Library\Don Norman\The Design of Everyday Things (2135)\The Design of Everyday Things - Don Norman.epub click "Show Details" for more information

Failed to connect to worker process

The debug log says,

calibre Debug log
calibre 2.55  embedded-python: True is64bit: False
Windows-8-6.2.9200 Windows ('32bit', 'WindowsPE')
32bit process running on 64bit windows
('Windows', '8', '6.2.9200')
Python 2.7.9
Windows: ('8', '6.2.9200', '', 'Multiprocessor Free')
Starting up...
Started up in 31.99 seconds with 1996 books
Worker Launch took: 10.3440001011

I don't know why it says Windows 8 -- I recently updated Windows 7 to Windows 10, and I've never used Windows 8 in my life!

Is it that the library is too large?

Any advice would be most welcome.

[eschwartz]

I don't know why it would cause this error message, but it should certainly cause an error...

Why are you using Google Drive with calibre? Do not do that... see the warning sticky thread in the Related Tools subforum.

[theducks]

C:\Users\Home\Google Drive\Calibre Library\Don Norman\The Design of Everyday Things (2135)\The Design of Everyday Things - Don Norman.epub

Google drive destroys the Calibre Library (title) folder name structure. It is in the FAQ
If you passed the Library (un zipped) thru GD, it probably has been damaged

[Innula]

I use Google Drive, and have done without problems for about 3 years, because it works well with the copy of Calibre Cloud Pro I have on my Android tablet (a Nexus 7 originally and more recently a Galaxy Tab S2).

However, I've just tried creating a new Calibre library in my C drive, adding one book to it and then trying to open that book, with exactly the same result and error message.

So I am not sure that the library's location is the problem.

ETA: I've just tried opening the Calibre Quick Start Guide in the library that was created when I re-installed Calibre, both from the main Calibre UI and also from the Windows context menu and selecting Calibre's e-book viewer app. Again, "Failed to connect to worker process"

[theducks]

Sounds like a variation of

http://manual.calibre-ebook.com/faq....windowshttp://
All I know is it works fine on my W10pro (x64) upgrade from W7pro

[eschwartz]

The worker process is being interfered with by something. Maybe an antivirus, maybe something else if you say you already tried disabling your antivirus.
(If I have too many things running and am low on RAM, the oom-killer kicks in, but otherwise linux is blessedly free of this insanity.)

The warning about Google Drive was just free advice. It will bite you eventually.

[Innula]

Thanks. As I said, I tried disabling the anti-virus but that didn't work. Calibre is also set as a trusted application for most purposes and if it tries to do something the AV is suspicious of, the AV notifies me and asks what to do next rather than silently blocking it.

I don't fully understand Windows 10 permissions, but everything looks OK with them and other e-book readers can open my e-books in that folder, so I don't see why Calibre shouldn't be able to.

I'm completely baffled.

As to using Google Drive or not, are there similar problems with Dropbox? Calibre Cloud works well with that, too, so it would be easy to switch.

[eschwartz]

Google Drive is the only cloud storage that silently modifies filenames with numbers in parentheses.

Dropbox is fine; that's what I use.

[BetterRed]

Originally Posted by Innula

I don't know why it says Windows 8 -- I recently updated Windows 7 to Windows 10, and I've never used Windows 8 in my life!

I think that's because the OS information is provided by a Qt library function. Qt doesn't recognise any version of Windows beyond version 8. But that is not the problem.

Originally Posted by Innula

Is it that the library is too large?

No - there are libraries of ~200,000 books, I have one approaching 80,000.

Did you try Safe Mode? That should eliminate most third party software

BR

[kovidgoyal]

That error literally means that calibre could not contact its worker process. Which means something is either preventing the worker process from running or blocking the worker process from using a pipe for communications. In my experience, the cause is always an antivirus/security program.

This error has nothing to do with the individual ebook you are trying to open. It will happen for *all* books until you figure out what is interfering with the worker process.

[Innula]

Thanks. I'm really puzzled. I did as BetterRed suggested and started in Safe Mode, and Calibre worked fine. So clearly it's something on my machine.

However, while I realise the anti-virus is the most likely candidate, I've just tried disabling my AV again and also MalwareBytes, and it still won't work. Plus I've been been using both Emisoft and MalwareBytes for a long time, and Calibre has always worked well before.

I guess I will have to work through applications methodically until I track down what's stopping it from working.

[BetterRed]

@Innula - is there anything in FAQ - calibre freezes/crashes occasionally? that may be relevant.

In Task Manager's Start-up tab you can Disable the start up programs. I would start by disabling half of them, and restart. If it calibre doesn't work disable the other half. If calibre still doesn't work then... hmmm - drivers, services, have a look to see if there are any 'oddball' services or drivers running.

Also have a look in Control Panel->Programs and Features to see if anything 'unusual' has been installed in recent times. Also check Windows updates, I got an update to my video card s/w the other day - it dumped bloat into startup and installed an unwanted shell menu extension, I gave both of them short shrift.

BR

[Innula]

I'll certainly try disabling things as BetterRed suggests, as soon as I get the time to.

However, there's something else I've noticed that may cast some light on the mystery -- I just don't know.

I use the editor Sublime Text 3 for coding, and it can check my syntax for me. Normally it's very quick but since I updated to Windows 10 it's really slow to complete. I mention this because these are the kind of debug messages I see.

Ignore the first few lines -- it's found 3 errors in the script "Wandering Robot 1.lsl" that I'm working on, and 2 things it wants to warn me about, and it's telling me where the script is saved and so on.

However, the references to Calibre 2 in the section beginning "[path:" are maybe significant.

I have no idea what the part of the message indicates, but Calibre is clearly something to do with it. Since Sublime Text's debugger has started running so slowly, and since it mentions Calibre, I wondered if there might be a connection.

If I can find a Sublime Text help group I'll ask there, too, what the message means, and report back here if there's anything interesting.

TOTAL:: Errors: 3  Warnings: 2
[Finished in 15.1s with exit code 3]
[cmd: ['C:\\Users\\Home\\AppData\\Roaming\\Sublime Text 3\\Packages\\LSL\\windows\\lslint.exe', '-p', 'C:\\Users\\Home\\Dropbox\\Wandering Robot\\Wandering Robot 1.lsl']]
[dir: C:\Users\Home\Dropbox\Wandering Robot]
[path: C:\ProgramData\Oracle\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\system32\wbem;
C:\Windows\System32\WindowsPowerShell\v1.0;
C:\Program Files\Calibre2;
C:\Program Files\Microsoft SQL Server\110\Tools\Binn;
C:\Program Files (x86)\Windows Kits\8.1\Windows Performance Toolkit;
C:\Program Files (x86)\Microsoft SDKs\TypeScript\1.0;
C:\Program Files\Microsoft SQL Server\120\Tools\Binn;
C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;
C:\Program Files\Cepstral\bin;C:\Program Files (x86)\Cepstral\bin;
C:\Program Files (x86)\Skype\Phone\;C:\WINDOWS\system32\config\systemprofile\.dnx\bin;
C:\Program Files\Microsoft DNX\Dnvm\;
C:\Program Files\Microsoft SQL Server\130\Tools\Binn\;
C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;
C:\WINDOWS\System32\WindowsPowerShell\v1.0\;
C:\Program Files (x86)\Calibre2\;
C:\Users\Home\AppData\Local\Programs\Python\Python35-32\Scripts\;
C:\Users\Home\AppData\Local\Programs\Python\Python35-32\]

[theducks]

You have both 32 bit and 64 bit calibre installed? This is valid, but can confuse Troubleshooting if you alternate versions when reporting (Logs) status.

Please be sure to use a single version for trouble shooting.
(Works in x64, but fails in 32bit is a proper reporting use of both)
Just be clear what version the reports are from
Both version us the same preferences
Both versions should NOT be launched (running) at the same time

[kovidgoyal]

That's just reporting your system path. The calibre installation directory is in that path. Nothing mysterious about it.