I have installed 7.0.1474 with virus definition 130215-1
and Avast want to update to vps_a32-a18-17.vpx.
I over and over again with several hours between the automatic update trials fail to perform the update.
The error message I get is “Ogiltig filsignatur. Installationen kommer att avslutas.”
My translation of it is “Invaldid file signature. The installation will be cancelled”.
Have anyone seen it, and do anyone know how to fix it?
tjena grabben 
try this, download full VPS and see if that changes anything http://www.avast.com/en-no/download-update
Halloj!
Thanks for a good advice. Now it is nicely updated. 