Ok…gotta try something different. Have been using Avast for the last couple of years and I love it. However, since downloading Avast 5, I am having great difficulty in getting it to update new virus definitions (current version is 100603-1 and I still have 100401-0). Program version is 5.0.462. It just refuses to update. Have tried uninstalling/reinstalling, turning off firewall, etc etc. Any other ideas or others with this same problem??
First download and install the latest 5.0.545 and see if that will fix it…
http://filehippo.com/download_avast_antivirus/
These are the update settings that works for me…
top right corner > settings > updates
ENGINE AND VIRUS DEFINITIONS
(ON) automatic updates
PROGRAM
(ON) automatic updates
UPDATE PARAMETERS
(OFF) i only connect to the internett using a dial up modem
(OFF) my computer is permanently connected to the internet
PROXY SETTINGS
(ON) auto detect (use internet explorer settings)
On some computers this have have worked
UPDATE PARAMETERS
(OFF) i only connect to the internett using a dial up modem
(ON) my computer is permanently connected to the internet
PROXY SETTINGS
(OFF) auto detect (use internet explorer settings)
Run a program update the latest is 5.0.545 like Pondus said. 
That’s the problem - it won’t update. I did just download the newest program version - however, again, the virus definitions are still out of date and will not update. Now the virus def version is 1100524-1
what firewall do you have ?
have you tried uninstalling it ?
I have PC Tools Firewall…I turned it off to try to allow Avast updates but that didn’t work. PC Tools and Avast worked together before, I really do not want to uninstall the firewall.
Yes but you can install it again, it is to see if the firewall is the problem…
Have you tried the settings in the post above and reboot ?
‘Refuse to update’, what does this mean? Does it notify you an error occured or nothing happended when clicking ‘uodate now’?
What I mean by refuses to update, I mean that when I select the “update” program or virus def button, it looks like it’s going to update, but than abruptly stops and tells you 3s or 4s (3 or 4 seconds I assume)…there is never any error message.
Until you get this fixed you can download the accumulated VPS updates here. (31 Mb!!)
http://files.avast.com/iavs5x/vpsupd.exe
asyn
Btw, which other security related programs are running on this machine…?
asyn
Other security related products running are Malwarebytes, Super AntiSpyware, Ccleaner, Ncleaner, Adaware
I don’t know about Ncleaner, but you should get rid of Adaware…!!!
All others run well with avast.
asyn
Ok, I will…I don’t really use it anyhow. Btw, thanks for the accumulated virus file link…that worked like a charm. I guess if I can’t get the updates to work I can at least do that.
You’re welcome…!! 
But we’ll get the autoupdate working…!!!
asyn
The one simple thing that solved a similar problem I had was to change the proxy setting to “Direct Connection” (as suggested by asyn)
Roger
I am having this problem too. I shut down my Comodo firewall and it still doesn’t update. When I go in to the Avast Summary page, it says my definition is out of date. When I click Update it goes through the process and says that my definition is “already up to date (current version 100614-0)”.
I am running on Vista Home Premium and it is Avast version 5.0.545. My Windows Security Alert says that Avast reports that it may be out to date.
Is this just a reporting problem and in actuality it is running the current definition update?
I ran the VPSUpdate file and that says “VPS database is already up to date”
robertl4, is your system time and date correct?
Any old antivirus in this machine? Any other security program that could interfere?
Which other security related programs are installed on that machine…??
asyn
Date and time are correct.
The only other security products I use are Comodo Firewall and the built in Windows Vista stuff. Avast has always worked perfectly with this exact same computer and set up until this newest upgrade. I haven’t used any AV product except Avast for several years.