AIS - Avast randomly blocks access to local network at home

Avast Free Antivirus / Premium Security
1

Both my wife and I use Avast Internet Security on our home PC’s, and over the past few weeks we have been losing Internet connectivity after a few hours of use. Usually a restart or reset of the router would resolve the issue, but today after a restart of both my PC and the router did not resolve the issue. I fiddled around and could not find the issue, until I disabled Avast temporarily and everything started working again. When the connectivity was lost, I could not even access my router over the network. I have been paying a subscription for the past few years and have been reasonably happy with Avast, but this is now becoming an irritation.
Does anyone know what may be causing this?

2

Hi,

Could you check to see if your Avast Firewall profile is set to “Private Network”
Open Avast Antivirus >then click on “Protection” > “Firewall”
and under “Firewall profile”, make sure that the arrow is pointing to “Private Network” (to be used when you are connected to a private, trustworthy network e.g. at home)

3

It is set to private network. I had an issue a few years ago after an update and it was because the firewall was set to Public. Now I make sure that it is set to Private when I do any troubleshooting.

I just had the issue again. I tried to open Youtube and sync my Onedrive, but there was suddenly no connectivity. I selected the “Disable for 10 minutes” option from the Avast menu, and my connectivity returned immediately. I then enabled all the shields and it is working fine again. I don’t know what is happening, but it is happening nonetheless.

4
  • Which Avast…? (Free/Pro/IS/Premium)
  • Which version…?
  • OS…? (32/64 Bit…? - which SP/Build…?)
  • Other security related software installed…?
  • Which AV(s) did you use before Avast…?
5

Hi,

To clarify, Is this issue occurring on two different PCs?
" losing Internet connectivity": is referring to only a specific browser or LAN connection?

A repair or re-install might help with this issue (core shield components might need to be fixed).

Repair:
Please follow the instructions as outlined here https://support.avast.com/en-ww/article/Repair-Antivirus
You’ll need to reboot your PC after repairing.

Reinstall:
To uninstall Avast Antivirus:

Download and run the uninstall utility from the link below:
https://support.avast.com/en-ww/article/10

To reinstall Avast Antivirus:

Download and run the relevant installation file from the link below:
https://support.avast.com/en-ww/article/87/
Avast Installation files
Click Install and follow the on-screen instructions.
Restart your PC to complete the installation.
Activate your Avast Antivirus product.

6

My PC finally broke and I built a new one. New hard drive, new Windows 10 installation from scratch. I installed AIS again, and the every few days this issue occurs. It in fact just happened again now. In Chrome I would see the “No Internet Connection” dinosaur, and nothing on my PC is able to connect to the Internet. I disable the Avast shields, and immediately my connection returns, upon which I turn the shields back on again and the connection is fine for a day or two.

This still happens to my wife’s PC as well (as recent as yesterday morning), and yes, we are on the same LAN connection. Neither repair nor reinstall did anything to solve the issue.

7
  • Which version of AIS…?
  • OS…? (32/64 Bit…? - which SP/Build…?)
  • Other security related software installed…?
  • Which AV(s) did you use before Avast…?
8

Set the firewall to Private

9

Set the firewall to Private
Already discussed under this topic. It is set to private. This is not my first rodeo.

- Which version of AIS…?
19.8.2393(build 19.8.4257.552)

- OS…? (32/64 Bit…? - which SP/Build…?)
Windows 10 Pro 64-bit, all up to date. Version 1909, Build 18363.657

- Other security related software installed…?
No.

- Which AV(s) did you use before Avast…?
Not relevant if you read this post. Old installs, new installs, same issue. Have been using Avast for a few years now.

10

You could try the latest beta: https://forum.avast.com/index.php?board=15

11

I am now running version 20.1.2397. While it is happening less, it is still happening a few times a week. I am extremely fed up at this point as I have been happily paying an Avast subscription for a few years now and then suddenly a few months ago this issue creeps in.
I ran a download through the night and it got stopped when Avast decided to terminate my connection again. Disabled the shields and immediately my connection came back on; re-enabled the shields and now it is like a ticking time bomb until Avast decided to stop my connection again. There must be some kind of log that Avast generates when something like this happens? Where can I find it?

12

Follow instructions: https://support.avast.com/article/33/ and post your File-ID here afterwards.