Avast 17 blocks Windows functionality

Avast Free Antivirus / Premium Security
1

Avast 17 blocks windows 7 programs/functions as Remote Desktop, Task Manager, commands through command strings, some links to use different system setting, no windows 7 activation data (licensed Windows activation is OK if Avast is stopped) and other issues related to Windows functionality.
Please, need in your help what are reasons.
Tanks in advance!

2
  • Which Avast…? (Free/Pro/IS/Premier)
  • Which version…?
  • OS…? (32/64 Bit…? - which SP/Build…?)
  • Other security related software installed…?
  • Which AV(s) did you use before Avast…?
3
  • Avast Free, v 17.3.2291
  • OS: Windows 7 SP1, x64
  • Windows Firewall, Internet Security settings acorrding to recommended level.
  • Only Avast was used last year. All data of previous AV was cleaned by a specialist to achieve correct Avast processing. I don’t remember a name of the AV already.

Previous version of Avast was processing correctly in the current environment.
No new security software was installed after Avast update to v 17.3.2291

4

Repair Avast:

  1. Control Panel → Add/Remove programs → Avast
  2. Click on ‘Repair’.
  3. Follow instructions.
  4. Reboot.
5

Repair is unhelpful

Whats done:

  1. Control Panel → Add/Remove programs → Avast
  2. Avast Repair run. Result: Microsoft Security Essentials conflicts with Avast, need to delete.
    NB. Very strange, because of no conflict with previous Avast version. Microsoft Security Essentials was installed in 2015 year, no updates of any setting/options/software or virus DB upgrades/schedules and so one since 2015.
  3. Deleted Microsoft Security Essentials.
  4. Avast Repair run again. Finished successfully
  5. Reboot.
  6. Test of windows functionality. The issues have place.
  7. Avast Repair with success and reboot one more time.

After all, Windows functionalities don’t work yet. Any idea?

6

First, be sure to get rid of all remnants of your prior installed AV(s)…!!
→ https://www.avast.com/faq.php?article=AVKB11#artTitle

Then:

  1. Download Avast Free Antivirus: https://files.avast.com/iavs9x/avast_free_antivirus_setup_offline.exe
  2. Follow instructions: https://www.avast.com/uninstall-utility (Run this tool for all prior installed Avast versions…!!)
  3. Reinstall Avast with the downloaded installer from point 1.
  4. Reboot.
7

I do it and inform you as soon as possible.
Just FYI: it was upgrade to v.17 proposed within Avast interface of previous version.

8

OK.

9

Hi Asyn,

Reinstall of Avast was unhelpful.
I followed instructions: remove under SafeMode via special Avast utility, reboot, install Avast downloaded via provided link, reboot.
But, issues are the same: no Windows licence, windows commands are impossible.

Do you have another idea? Maybe, it’s easer to install previous version instead of v.17.4?

10

Follow instructions: https://www.avast.com/faq.php?article=AVKB33#artTitle