7. evolution 패키지는 설치할 수 있는 후보가 없습니다

/etc/apt/sources.list

에 아래의 텍스트를 복사해 붙여넣고 apt-update를 실행하여 해결

 

#deb cdrom:[Ubuntu 20.04.4 LTS _Focal Fossa_ - Release amd64 (20220223)]/ focal main restricted # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://kr.archive.ubuntu.com/ubuntu/ focal main restricted # deb-src http://kr.archive.ubuntu.com/ubuntu/ focal main restricted ## Major bug fix updates produced after the final release of the ## distribution. deb http://kr.archive.ubuntu.com/ubuntu/ focal-updates main restricted # deb-src http://kr.archive.ubuntu.com/ubuntu/ focal-updates main restricted ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://kr.archive.ubuntu.com/ubuntu/ focal universe # deb-src http://kr.archive.ubuntu.com/ubuntu/ focal universe deb http://kr.archive.ubuntu.com/ubuntu/ focal-updates universe # deb-src http://kr.archive.ubuntu.com/ubuntu/ focal-updates universe ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu  ## team, and may not be under a free licence. Please satisfy yourself as to  ## your rights to use the software. Also, please note that software in  ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://kr.archive.ubuntu.com/ubuntu/ focal multiverse # deb-src http://kr.archive.ubuntu.com/ubuntu/ focal multiverse deb http://kr.archive.ubuntu.com/ubuntu/ focal-updates multiverse # deb-src http://kr.archive.ubuntu.com/ubuntu/ focal-updates multiverse ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://kr.archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse # deb-src http://kr.archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. # deb http://archive.canonical.com/ubuntu focal partner # deb-src http://archive.canonical.com/ubuntu focal partner deb http://security.ubuntu.com/ubuntu focal-security main restricted # deb-src http://security.ubuntu.com/ubuntu focal-security main restricted deb http://security.ubuntu.com/ubuntu focal-security universe # deb-src http://security.ubuntu.com/ubuntu focal-security universe deb http://security.ubuntu.com/ubuntu focal-security multiverse # deb-src http://security.ubuntu.com/ubuntu focal-security multiverse # This system was installed using small removable media # (e.g. netinst, live or single CD). The matching "deb cdrom" # entries were disabled at the end of the installation process. # For information about how to configure apt package sources, # see the sources.list(5) manual.