I have a problem with Avast 2016 on a Windows 10 computer. After I installed it on a new computer, one of the other user accounts on the computer can no longer access certain sites. E.g. google.co.uk or youtube.com or bing.com are all unreachable from the affected account, but work perfectly fine from my own account that I used to install Avast.
If I turn off the Webshield temporarily then those sites become accessible again from the affected account. But there are no notifications from Avast while the Webshield is on that it is responsible for blocking those sites; the browser simply fails to connect to the pages. The problem affects Chrome, Edge and Internet Explorer.
There is also a new problem that coincided with this that is not remedied by turning off the Webshield. Sign in to Office365 is impossible on the affected account, regardless of the state of the Webshield, or any of the other real-time services, but works fine from my own account.
Did you install avast while logged in a true administrator and installed it for all user accounts ?
What exact OS/SP ?
What exact version of avast ?
Any other security (related) software installed ? (or was there)
Is Windows Defender disabled ?
What are the different settings for the user accounts (if there are any) ?
Already performed a repair of avast ?
Already performed a clean installation of avast ?
Checked for malware on the entire system ? https://forum.avast.com/index.php?topic=53253.0
Is there anything in one (or more) of the avast log files that perhaps tells why it is blocked ?
I installed Avast from an administrator account for all users.
The OS is Windows 10 Home. It’s up-to-date as of 11h00 on 22-11-2016.
The computer came with some McAfee software installed. Avast identified it as needing to be removed; I allowed it to be removed.
Windows Defender isn’t active.
The first account (where things work ok) is an administrator account. The second account (which has problems) is a child account associated with the first; there are parental controls active on the child account.
I have not repaired, uninstalled/reinstalled Avast (yet).
Avast detects nothing in its virus scan, including a boot-time scan. Malwarebytes Anti-Malware finds nothing either.
The Avast scan logs simply confirm that it found nothing. I can’t see / find any log associated with the Webshield service.
The Office 365 problem was unrelated (as far as I can tell) to anything to do with Avast.
The google.co.uk & youtube.com problem persists, even after uninstalling and reinstalling Avast. (I didn’t see the reply above about removing McAfee software with a separate removal tool, before I tried that).
I have discovered that the Webshield does not need to be entirely deactivated in order to allow those websites to be browsed; it is sufficient to disable scanning for https sites.
I still have no idea why it needs to be disabled for that “normal” user, but everything works just fine for the administrator account which installed Avast in the first place (even when scanning is enabled for https sites).