Avast seriously messing up multiple PCs, cannot launch any app

Avast Free Antivirus / Premium Security
1

Hello, 3 issues with Avast since yesterday’s update:

1) On my main PC I manually clicked - Update - Program and new version 21.3.2459 (build 21.3.6164.561) started installing

  • during install, Avast popped up virus threat - blocking itself - uninstaller in Avast folder (cannot tell you the exact name, it is not in history once removed from chest)
  • blocked it, then checked virus chest what it actually is, what’s the location and whitelisted + added exception
  • during this whole time Avast locked itself up (looped) with this “virus” warning and whatever you did, pop-up warning was there all the time
  • I had to restart PC to get rid of it => seems solved, except part 3 of issue

2) Dad’s PC - seems like yesterday Avast tried to update in the background and since yesterday dad couldnt launch any app at all - my logic explanation is Avast experienced similar issue like myself and it locked itself up, but because he doesn’t have manual decision pop-up warnings enabled, he didn’t even know it was Avast all along, PC restart didn’t help

  • tried to uninstall via Programs and Features - failed, it doesn’t do anything because Avast is stalling any process launched, Avast service also couldn’t be stopped via services.msc / Task Manager
    - had to boot up in Safe Mode - uninstall Avast through Programs and Features, restart => solved the issue, Windows and all apps work normally since then

3) Took me some time to figure out the culprit, but since yesterday if I have Avast shields on, I cannot launch Diablo 3 at all, black screen, then trying to connect to server - D3 app stops responding and I have to shut it down.

  • when I disable Avast shields, it works fine.
    (Also tried x86 version and D3 x86 works ok, just D3 x64 is broken with Avast shields up)

My PC Win10 20H2 build 19042.867
Dad’s PC Win7

This needs to be addressed asap, because if my assumption is correct, it is f**k up big time :o - Avast basically tries to “update” itself in the background and makes PC unusable
-Cheers from Czech Republic, 15+ years user of Avast 8)

2

Tried looking for uninstall file mentioned in #1 with UndeletePlus but was unable to find it, already overwritten by other file.

W10 .nfo file here https://uloz.to/file/HUGefWDd9IdT/pc-nfo-nfo
(log will be auto deleted in one month)

3

Hi,

the temporal fix was released in the VPS yesterday.

Can you let us know if the issue still persist when the AntiRootkit is enabled?

Thanks,
PDI

4

Hi Jeuffrey,

can you please provide us the support package from your 2 machines where you have seen the detections?

See https://support.avast.com/en-ww/article/Submit-support-file

Thanks,
PDI

5

Sorry for late reply, support package sent.

#3 issue solved

#1 and #2 I cannot reproduce, I would require full offline installer of previous Avast version.

6

#1 and #2 were caused by false positive file during Avast update:

C:\PROGRAMZ[b]AVAST\SETUP\UNINSTALLEXCHANGE.PS1[/b]

7

Hi Jeuffrey,

thank you for pointing out the script which was detected.

Regards,
PDI