Calibre Reader

[pootytang]

For a couple of months unable to launch reader. Error is Qt WebEngine Render process has crashed. Reader had worked for years, until now.

I've rebooted, and tried reinstalling to a different local drive without any success. I also updated versions. I have searched around and while there are a few messages on this, I have not be able to decipher the limited suggestions.

Any one have a clear course of action?

Thanks

Pooty

[kovidgoyal]

This is caused by incompatibilities between Qt WebEngine (used by the viewer and editor) and the graphics drivers
on your system. Try updating the graphics drivers, if that does not work, you can try disabling hardware acceleration
by setting the environment variable QTWEBENGINE_CHROMIUM_FLAGS="--disable-gpu"

[pootytang]

Thanks very much for the reply. After searching for how to do what you advised, I am getting the following error message when trying to set the envir0nmental variable: "A path component can't contain any control characters nor any of the following:/*<>|

I was trying to add to either the Calibre path, or as a new item:
QTWEBENGINE_CHROMIUM_FLAGS="--disable-gpu" in Win 11 Environmental Variables.

I deleted and installed current graphics drivers without any change.

Thanks

Pooty

[DNSB]

Originally Posted by pootytang

Thanks very much for the reply. After searching for how to do what you advised, I am getting the following error message when trying to set the envir0nmental variable: "A path component can't contain any control characters nor any of the following:/*<>|

I was trying to add to either the Calibre path, or as a new item:
QTWEBENGINE_CHROMIUM_FLAGS="--disable-gpu" in Win 11 Environmental Variables.

I deleted and installed current graphics drivers without any change.

Thanks

Pooty

How did you attempt to enter the QTWEBENGINE_CHROMIUM_FLAGS environmental variable? A simple search in the search box for environment brings up a link to the Edit system environmental variables. After that, under system variables, enter QTWEBENGINE_CHROMIUM_FLAGS as the variable name and --disable-gpu as the variable value. Click OK a couple of times and you're done.

See attached image.

[pootytang]

I must be dense. Found what you have pointed me to and attached is a pic of the variable. Tried rebooting after change, yet still getting the Reader error pointing at QTWEBENGINE crashing. Here is variable and error message.

Thanks Much

[kovidgoyal]

Then your issue willl likely be some software interfering. Try rebooting in safe mode and see if the viewer works.

[pootytang]

Thanks again.

I booted to safe mode (with networking) and got the same QTWEBENGINE error message. I assume this is some setting or corruption in my Win 11 install?

The reader is not critical to me as I use it only to have a quick peek of a new book that I'm not yet ready to read in full. Is there an alternative to have Calibre start a 3rd party reader when double clicking on a book in my library? I know I can have Calibre pop open file explorer and execute a different reader that way. I guess I'm more curious about my issue since the reader worked for years, and wonder what I changed to cause this.

Thanks again

Pooty

[BetterRed]

Originally Posted by pootytang

Is there an alternative to have Calibre start a 3rd party reader when double clicking on a book in my library?

Uncheck the format in the Preferences->Behaviour->Use calibre viewer for: list.

BR

[kovidgoyal]

Yeah its most likely something off in your install. you can try running

calibre-debug -w

in a command prompt to start the viewer in deug mode, it might give us more info though if the problem is in Qt WebEngine, it probably wont.