私はPop!_OS 18.04 LTSを使用しています。
aptエラーが発生したとき。下記をご覧ください。
sudo apt install -f
Reading package lists... Done
E: The value 'buster' is invalid for APT::Default-Release as such a release is not available in the sources
sudo apt dist-upgrade
Reading package lists... Done
E: The value 'buster' is invalid for APT::Default-Release as such a release is not available in the sources
sudo apt autoremove --purge
Reading package lists... Done
E: The value 'buster' is invalid for APT::Default-Release as such a release is not available in the sources
sudo apt install synaptic
Reading package lists... Done
E: The value 'buster' is invalid for APT::Default-Release as such a release is not available in the sources
ベストアンサー1
sudo rm /etc/apt/apt.conf.d/defaultrelease
sudo apt update
問題を解決しました。