Calibre not starting in Win 10

[abaruffo]

Hello all,

I'm an occasional Calibre user. I read (mostly) epub's in my Win 10 laptop. A few weeks ago, Calibre stopped working: it simply doesn't start without any error or warning.
I've tried to remove/reinstall various versions, 32 and 64 bits, but without success.
I also "whitelisted" the Calibre executable in my antivirus (F-secure), but again, with no luck.

Following the FAQ "calibre is not starting on Windows?", I tried running Calibre as Administrator: nothing.
Finally, I'm asking you fore help.
Here is the output of "calibre-debug -g"

C:\Program Files (x86)\Calibre2>.\calibre-debug.exe -g
calibre 5.8.1  embedded-python: True is64bit: False
Windows-10-10.0.19041 Windows ('32bit', 'WindowsPE')
32bit process running on 64bit windows
('Windows', '10', '10.0.19041')
Python 3.8.5
Windows: ('10', '10.0.19041', '', 'Multiprocessor Free')
Interface language: None
Turning on automatic hidpi scaling

Any help will be appreciated. Thanks

[georgemk]

Reboot Windows into safe mode and see if it runs there.

If it does then some process is causing issues in normal mode.

[kovidgoyal]

according to that its running, its probably just offscreen/on a different monitor.

[abaruffo]

Originally Posted by kovidgoyal

according to that its running, its probably just offscreen/on a different monitor.

Thanks for the reply.
No, Calibre is not running. I checked with Task Manager and it's not there. It briefly appears during startup and then goes away.

[abaruffo]

Originally Posted by georgemk

Reboot Windows into safe mode and see if it runs there.

If it does then some process is causing issues in normal mode.

Thanks for the hint. Indeed Calibre runs in safe mode.
Any suggestion on how to identify the conflicting process?

[georgemk]

99 times out of a hundred it is the anti virus software. You need to disable F-Secure and then try again.
I know you said you told F-secure about 1 of the many calibre exes but please try this. calibre is more than just 1 single executable and needs access to many things in its installation directory and its subdirectories.

[abaruffo]

There is no single "On/Off" switch for F-Secure. However, I disabled as many "features" as possible: still no visible change.
I disabled a lot of other services (e.g. one drive) and exited almost all programs (just kept Firefox to post on this forum). Again, no luck.
Thank you very much @georgemk, @kovidogyal for your help .
I will probably give up now.

[georgemk]

Can you just tell F-Secure to ignore the whole Calibre installation directory and its sub-directories?
https://help.f-secure.com/product.ht...818F-latest-en

[abaruffo]

Yes, thanks for the suggestion. I forgot to tell (sorry), but I already tried that.
Now, I tried again adding to the "exclusion list" some sub dirs of the installation directory (app, app\bin, app\plugins, etc). Still no luck.
Honestly, I would have expected to get a message from the AV if it was blocking anything. Also, the "quarantined" and "blocked" files lists are empty.
Finally, removing all Calibre dirs from the "exclusion list" and performing a manual AV scan turns up nothing (298 items scanned, not harmful items found).
Looks like Calibre is clean for F-secure.

[JSWolf]

Given that Calibre runs in safe mode, go to Taskmanager and then the Start-up tab and turn everything off from running. After a reboot, if Calibre works, activate one, reboot, and try Calibre again. Keep doing this until Calibre stops working. Then you'll know what's causing Calibre to stop running.

However if after you've disabled all in Start-up and Calibre doesn't run, it could be some service installed along with some program.

Another thing to try if you cannot find what the problem is is to uninstall your AV because some AV needs to be gone (uninstalled) to stop it's shenanigans.

[kovidgoyal]

Originally Posted by abaruffo

Thanks for the hint. Indeed Calibre runs in safe mode.
Any suggestion on how to identify the conflicting process?

Look at the system event logs, if those are not illuminating (which is quite likely) you are left with the good old, disable one service, reboot, test, repeat cycle.

[abaruffo]

@kovidgoyal: had a look at event logs, found nothing illuminating (not even relevant...)
@JSWolf: disabled all entries in Task Manager's "Startup" tab, but Calibre still doesn't start.
Thanks for your advice.

[abaruffo]

Got a clue.
Most of the time, I connect my laptop to an USB-C docking station, hooking up a wireless keyboard/mouse and two screen.
If I detach the docking, Calibre starts. If I re-connect the docking, it keeps running. If I exit Calibre while still docked and re-start it, it doesn't work.
So, nothing to do with safe mode, AV or conflicting processes, it's the docking.
Maybe this has to do with the last message before exiting "Turning on automatic hidpi scaling"?

Note that I work this way since many years and Calibre used to work OK. Maybe something has changed in the drivers.

[Bookstooge]

Originally Posted by abaruffo

Got a clue.
Most of the time, I connect my laptop to an USB-C docking station, hooking up a wireless keyboard/mouse and two screen.

Originally Posted by kovidgoyal

according to that its running, its probably just offscreen/on a different monitor.

So does calibre NOT start up when you're hooked up to the docking station as well?

[abaruffo]

Problem solved.

I visited my laptop vendor site and found an update for the dock driver (it didn't show up in Windows update), installed it, and now Calibre is back up and running also when the laptop is docked.

Thank you all for providing suggestions which eventually led to the right track,