I used 4.8 for nearly a year, before getting the notification that my free license was about to expire. I found the new version (5.0) available and installed, allowing it to overwrite the older version. I can't get it to update either! I use Windows Firewall, in addition to Spybot SD and Malwarebytes. I added ashUpd.exe to the Exceptions, since "avast.setup" is nowhere to be found in the directory. I too downloaded and attempted to update from the virus definition package. That didn't work either. I even attempted updating with my firewall, Spybot SD and Malwarebytes disabled. To no avail!
When I attempt to update manually, from the user interface, I get the following:
url=guide.opendns.com%2Fhttp%3A%2F%2Fguide.opendns.com%2F%3Furl%3Dguide.opendns.com%252Fhttp%253A%252F%252Fguide.opendns.com%252F%253Furl%253Dguide.opendns.com%25252Fhttp%25253A%25252F%25252Fguide.opendns.com%25252F%25253Furl%25253Ddownload662.avast.com%252525252Fhttp%2525253F%2525252Fdownload662.avast.com%2525252Fiavs5x%2525252Fservers.def
The average time between update tick and error message is about 9 seconds.
I CAN update the program from the Add/Remove Program utility. I can also update with the virus definition package, while in safe mode.
And, even though it IS updated, Microsoft Security Center reports that the virus definitions are probably out of date...
Win XP Pro sp3
AMD processor LE-1600
2.21 GHz, 2 GB RAM
HS Cable