Avastsvc uses 25% CPU all the time

Hi
I need your help. Since the beginning of the week when I booted my computer mainly for the first time, after some minutes when the avastsvc began to work, I could visualize on the task manager that the avastsvc was consuming 25% cpu constantly. I didn´t make changes on my computer.Only 2 things happened different from always:

a) A new firefox update
b) the free license was going to expire, now I renewed it but the problem continues. Could be possible that you would made changes on the behavior of the shields or real time monitoring? I will be very grateful if you help me.

Many thanks!

  • Which Avast…? (Free/Premium)
  • Which version/build of Avast…?
  • OS…? (32/64 Bit…? - which SP/Build…?)
  • Other security related software installed…?

See https://forum.avast.com/index.php?topic=299096.0

avast free windows 7 64 bit 17.9.2322 avast version
I dont have other security software installed.
What I notice now is that the problem appears only on the first boot and when I open any program browser, explorer,etc. At this moment the avastsvc begins to work and stuck on 25%.
if I restart the computer the problem dissapears but this is not a solution.

First, be sure to get rid of all remnants of any prior installed AV(s)…!!
https://support.avast.com/article/11/

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.

You have the exact same problem as me and Blues Brothers on https://forum.avast.com/index.php?topic=299096

You’re CPU is quadcore, right? Mine is duo.
The problem seems to be “avastsvc uses one whole core for itself”.
Try a full system scan and check if :

  • scan hangs on svchost
  • CPU usage goes higher up at that time

I tried a full scan and the avastsvc hangs with 25% of cpu.The svchost is ok.You could resolve the problem?

No solution found at the time except installing avast 21 (last version)
I’m waiting for my saviour in the other thread i linked in my previous message.

Thank you for all your help!! Could be possible that there could be a permission problem when avast trie to scan system files on background? because one week ago it was going well.

What I’m noticing is that we are at least tree users having the same problem on windows 7 or old avast versions at the same time!

I hope that avast could resolve the problem.I always had problems when i had the configuration setting to update automatically For that reason I turn off the automatic updates. I forgot to tell you that you are right My computer is an all in one hp touchsmart 610 intel core i5

I took the liberty to create a new thread about your/my/Blues Brother’s problem :
https://forum.avast.com/index.php?topic=300638.msg1651086#msg1651086

You will find a temporary solution to our problem, and a more definitive one.

Many thanks for creating the new thread.Can’t install the new version because I have windows 7 Sp1.Please solve the problem with the old versions.

So why can’t you install a later version ?

I can’t see how things would change if you are still using an old version of Avast, which essentially hasn’t changed as Avast doesn’t modify old (unsupported) versions. So what else on your system has changed recently ?

The version you have is very old and I can’t see Avast devoting the time trying to find where the problem might in an unsupported version of avast.

Even with win 7 SP1 you should be able to install Avast 18.8 (some had to go back to avast 18.5), the last version to support winXP and Vista and you have Win 7, so theoretically you should be able to go beyond that.

Are you not able to install Win 7 SP2 - https://www.google.co.uk/search?q=windows+7+sp2 ?

Many thanks for your help but if avast wants that all users update to the last version how I know that this version that you mention will not have the same problem.
I turn on another computer with windows 7 and an old version of avast and it happens the same problem.Last monday it was going well.It is obviously that avast change something.

The problem goes from Avast 9 to 17 : i have the same problem and just installed avast 17 on a factory system image from 2013 with an offline VPS update (28/08/2021).

The first version which should be ok (as far as my tests go on win7 SP1) is avast 19.

By the way, edialchu, avast 19 is available on filepuma (search on google : “site:filepuma.com avast 19”) and you can install it. Only some recent avast21 versions ask for a win7 update.

The real problem is :

  • yes we could upgrade to win7SP2 or even win10
  • yes we could upgrade to avast19 or even avast21

But in my long experience, there is no update (OS or software) which makes things lighter. And i tried avast 19, 20, 21 : they’re all heavier than avast 9 (surpriiiiise). Moreover, avast9 is more customisable.

Everyone does not own a powerful PC, nor does want/afford one.
My PC is a 2013 netbook, which was already considered as “weak” at the time.
My weak PC is functional and i refuse to throw it away or make it kneel because of “forced” updates. Reasons : money, environment, principles.

Our problem is triggered by a VPS update, because at least three users around the world had the same problem the same day. We are not asking complete maintenance on old avast versions.

I’m pretty sure there’s just one single virus definition which poses a problem between two consecutive days.

The short answer (as an avast user) is no I can’t, as I haven’t any idea why this has all of a sudden happened. To you, my comment about avast 18.8 being the last supported version for XP didn’t work for some (including myself) and they had to go back to 18.5 to resolve it.

At the time, because this was the last supported version Avast were considering a fix (if they could find the problem) on the last supported version. This however never happened to my knowledge. So there is history there of not fixing old unsupported versions.

Virus definitions, or rather Engine and virus definitions are regularly updated, so I don’t know if they would/could deliver an Engine Update on very old versions.

The simple fact that old OSes and Antivirus versions leave the system less well protected as time and malware marches on. What the user is to do about that really is a user choice.

Switching AVs is an option, but will that AV support the old OS in its current version or would you be faced with the same situation.

The same day that began the problems 25 August it was the announcement of the new version:
https://forum.avast.com/index.php?topic=299095.msg1649279#msg1649279

Which give that you still have avast free 17.9.2322, means you haven’t got avast 21.7, so that shouldn’t have had any impact.

I assume (dangerous) that you have avasts program update set to Manual (which I have) to prevent automatic program updates ?

You are right it shouldnt have had any impact but it had not only for me but for more people.
My computer’s parents have the same problem also my husband’s computer all with windows 7 and different old avast versions and the problem appeared on 25 August a coincidence? I don’t think so. 4 computers that suddenly go wrong I don’t know what to do.The situation is distressing.
I have set to manual avast updates because in the past when I had set on automatic the computer didnt start again the screen went black and the same problem happened me on different computers so that was the solution I found on that time to set it manually.I hope that avast could review what happen.