apt-log.txt

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

Reading package lists...
Building dependency tree...
Reading state information...
Package ttf-freefont is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package ttf-liberation is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package synaptic is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package gksu is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'gksu' has no installation candidate
E: Package 'ttf-freefont' has no installation candidate
E: Package 'ttf-liberation' has no installation candidate
E: Package 'synaptic' has no installation candidate