yaourt is a pacman helper and as such it is unsupported. Therefore the
appropriate channel to get the help you need is the aur-general
mailing list. I'm copying this to them.
On Fri, Jun 20, 2014 at 3:44 PM, Viktor G <meilenweitvoraus(a)gmail.com> wrote:
> I can't update yaourt and package-query via pacman -Syu because I get
> an error which says the package is broken and there's a problem with
> the PGP signature. 
> I can ignore this package but I think it's not a good solution.
> What can I do?
> Thanks for your answers.
> -- Vik
> : Original Error (in German): "Datei
> /var/cache/pacman/pkg/package-query-1.3-1-x86_64.pkg.tar.xz ist
> beschädigt (Ungültiges oder beschädigtes Paket (PGP-Signatur)).
> Soll die Datei entfernt werden? [J/n]"