Comment 1 for bug 1884525

> RuntimeError: Failed to load the progress_indicator C extension, with error: PyCapsule_GetPointer called with incorrect name

Your error indicates that the program has been built or installed
incorrectly.

> Installed using "sudo apt-get install calibre"

This means that the problem comes from the apt-get distributors (that is
to say, the Lubuntu packaging team, which apt-get downloads from).

If you instead download the standalone binary builds of calibre from
https://calibre-ebook.com/download_linux I suspect you will find that
they work fine.

Please report this bug to the Lubuntu developers. As a member of the
Debian/Ubuntu family of Linux distributions, they usually prefer bugs to
be reported directly to them -- then they will evaluate the bug, try to
figure out if it is a Ubuntu bug or a bug in calibre itself, and either
fix the bug within Ubuntu or forward it to the calibre developer.

(If, however, you have a problem with the standalone binary builds I
mentioned, then please report those here. Those do receive official
support directly from the calibre developer, and additionally can be
used as a test to reproduce bugs and determine if they are calibre bugs
rather than Ubuntu bugs.)

 status invalid