I have followed this plan and avast! still does not update, either manually or automatically.
I have turned off the Windows firewall.
The symptoms are exactly as they were before, the update status bar moves perhaps a quarter inch then stops.

I am indeed running a paid version of AIS, now after the removal and re-install it is version 6.0.1367 with definition version 111128-1 dated 11/28/2011 8:02:42 AM

Next step?