You can change the folder calibre is installed into from the default (/opt) like this: On servers, if you get an error about a missing libEGL, you might need to install some OpenGL packages such as libegl1 and libopengl0.If you get an error Could not load the Qt platform plugin xcb you are missing some needed X11-XCB libraries, such as libxcb-cursor0 or libxcb-xinerama0, for details see here.If you get an error about Wayland when running calibre from the terminal and calibre does not start, run calibre as QT_QPA_PLATFORM=xcb calibre which will prevent it from using Wayland.You need GLIBC 2.31 or higher and libstdc++.so.6.0.28 (from gcc 9.3.0) or higher to run calibre.Alternately, simply deleting the installation folder will remove 99% of the installed files. You can uninstall calibre by running sudo calibre-uninstall. You must have xdg-utils, wget, xz-utils and python installed on your system before running the installer. Sudo -v & wget -no-check-certificate -nv -O- | sudo sh /dev/stdin If you still want to proceed, pass the -no-check-certificate option to wget, like this: If you get an error about an untrusted certificate, that means your computer does not have any root certificates installed and so cannot download the installer securely.