![参见 apt-secure(8)](https://linux22.com/image/1182179/%E5%8F%82%E8%A7%81%20apt-secure(8).png)
当我输入时sudo apt update
我得到了这个:
Hit:1 http://mirror.0-1.cloud/ubuntu focal InRelease
Hit:2 http://mirror.0-1.cloud/ubuntu focal-updates InRelease
Hit:3 http://mirror.0-1.cloud/ubuntu focal-security InRelease
Hit:4 http://ppa.launchpad.net/go-for-it-team/go-for-it-stable/ubuntu focal InRelease
Hit:6 http://ppa.launchpad.net/linuxuprising/apps/ubuntu focal InRelease
Hit:7 http://packages.microsoft.com/repos/code stable InRelease
Hit:8 http://ppa.launchpad.net/otto-kesselgulasch/gimp/ubuntu focal InRelease
Ign:9 https://repo.protonvpn.com/debian stable InRelease
Hit:10 https://brave-browser-apt-release.s3.brave.com stable InRelease
Hit:11 http://ppa.launchpad.net/teejee2008/timeshift/ubuntu focal InRelease
Hit:12 https://download.sublimetext.com apt/stable/ InRelease
Err:13 https://repo.protonvpn.com/debian stable Release
Could not handshake: Error in the pull function. [IP: 104.26.8.21 443]
Hit:14 http://ppa.launchpad.net/xuzhen666/gnome-mpv/ubuntu focal InRelease
Get:5 http://repo.mysql.com/apt/ubuntu focal InRelease [5,309 B]
Err:5 http://repo.mysql.com/apt/ubuntu focal InRelease
Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?)
Reading package lists... Done
E: The repository 'https://repo.protonvpn.com/debian stable Release' no longer has a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Failed to fetch http://repo.mysql.com/apt/ubuntu/dists/focal/InRelease Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?)
E: The repository 'http://repo.mysql.com/apt/ubuntu focal InRelease' is no longer signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
我该如何解决这个问题?任何帮助都将不胜感激。