Avast free antivirus behind proxy - manual update works - automatic update fails

Avast Free Antivirus / Premium Security
1

Dear All,

I see some strange behaviour of avast free antivirus 2015 and 2016.
There is a non transparent squid proxy server in my LAN.
My PCs (win7, win8, no desktop firewall) are well configured to use is for browsing etc (automatic detection via wpad)

As I saw no “automatic proxy feature” to configure in my avast installation, I configured the proxy settings manually.
My MANUAL updates work fine.

But AUTOMATIC updates do not work, after several days I still see the version I updated manually.
When I click “update manally”, I get updates to the latest version.

I analyzed this automatic update behaviour on two of my PCs with wireshark.
This is what I saw:

  • dns queries and answers for avast domain names
  • tcp syn packets directly to Avast Internet IPs
  • NO packets to my proxy server.

So obviously the avast automatic update directly tries to connect to the update servers , ignoring the proxy settings.
I saw the same behaviour with the register feature in the avast GUI → no connecton possible.

So I would like to ask you two questions:

  1. is there anyone using avast free antivirus 2015/2016 behind a proxy without the problems i described?
  2. does anyone of you have an idea how to solve or workaround the behaviour I saw?

Thanks a lot!
Sepp

2

Setting up the proxy details correctly in avast should work.

3

Dear Eddy,
thanks for your reply!

As my manual updates in the GUI work, I guess I inserted the proxy settings in the Avast GUI at the right place in the right way :wink:
By the way: a manual update with the command line tool “ashupd.exe” also works as designed, it utilizes the proxy information perfectly.

The only one ignoring proxy settings seems to be automatic updates :slight_smile:

You wrote: “Setting up the proxy details correctly in avast should work.”
Have you seen avast free antivirus 2015/2016 working correctly with proxy settings and automatic updates?

Greetings,
Sepp

4

Yes, I have seen it work in/with 2015 lots of times.
I used to have a computer (related) service and installed avast 100’s of times, including for people who use a proxy.
I have not seen it working with 2016 simply because I never have installed that version.

I suggest you try it with a other proxy server and see if that is working.
If it is, the problem is with the current proxy server.