I tried to update my system on Xubuntu : sudo apt-get update && sudo apt-get upgrade.
I got this error message :
E: Le pilote pour la méthode /usr/lib/apt/methods/bzip2 n'a pu être trouvé.
In english the driver for the method /usr/lib/apt/methods/bzip2 can't be found.
I checked the folder :
$ ls /usr/lib/apt/methods/ cdrom copy file ftp gpgv gzip http https mirror rred rsh ssh xz
Actually for the moment, APT can't install anything cause it can't unzip with bzip2 : the method doesn't exist inside the proper folder.