pacman -S xfce4-goodies fail

[doherty pete <nishizawa23@xxxxxxxxx>]

when i input pacman -S xfce4-goodies

many information like this

xfce4-xkb-plugin-0,5.3.3-4_x86_64.pkg.tar is invalid or corrupted
...
...

how to resolve this?
-- 
pete_doherty