It would seem to be an artifact of the naming of the packages in /var/lib/apt/lists, and I attach a screenshot of a Terminal window showing a [partial] 'ls -l' of that directory, together with a ciew of the error dialogue generated by Synaptic Package Manager.
My suspicion is that the -en%5fGB part of the name, more specifically the %5f part, is causing problems ...
This issue also affects me, on Linux Mint 15.
It would seem to be an artifact of the naming of the packages in /var/lib/apt/lists, and I attach a screenshot of a Terminal window showing a [partial] 'ls -l' of that directory, together with a ciew of the error dialogue generated by Synaptic Package Manager.
My suspicion is that the -en%5fGB part of the name, more specifically the %5f part, is causing problems ...