I’ve been reading this forum and it seems that there’s a lot of people here are having the same problem with high CPU usage with their computers. I think I may know what causes it - I don’t know how to fix it but may be a staff member/Avast software developer can investigate. Here’s my scenario:
I’ve been using Avast free antivirus version 18.8.2356 (build 18.8.4084.0 - release date 11/15/2018) ever since it first came out on my Windows 7 Home edition SP1 64-bit laptop with no other additional security software installed except the default Windows Defender, and I have it set on manual update for both the virus definitions and the program. I occasionally update the virus definitions manually whenever they’re out of date and it’s been working OK for 3 years until a couple of weeks/10 days ago when I manually update the virus definitions version 210825-8 (release date 8/25/2021 9:16:11 AM), and immediately (well, may be not immediately but a few minutes later since I didn’t notice it right away until my laptop started to run slowly) AvastSvc.exe jumped at 25% CPU usage and keeps running that high ever since.
In short, since I didn’t install any new software on my laptop for years and I’ve been using the same version of Avast also for years, therefore I think there must be something in the new virus definitions that cause it. I hope this sheds some light on the problem.
As I wrote on another topic since 25 August 2021 many computers with w7 and older versions of avast(avast 15, 17.18) began to have this problem.I think that the cpu goes up to 25% when it makes the rootkit scan.Also if you try to make a quick scan or full scan to all the computer the cpu goes up to 25% and never goes down because of the rootkits analyze. If you make a scan on a file or folder it goes ok. I dont know if it could be a problem of the virus definition update of August 25.
I know that your recommendation is to update to the last version but not all the people has a computer with the requirements to do it . Please we need your help in all this week I know 10 cases of computers with w7 that have this problem.The problem happens on the first boot then on the second boot it goes ok cpu 0%.Next day same problem first boot 25% second boot 0%.I will be very grateful if you help us.Thank you!!
First thank you so much for reviewing the problem for the old machines.I updated on 2 computers and it went ok. Iam testing on the others computers yet.
If appears the problem I will let you know.Many thanks again for your help!!! Iam very grateful!!!
Unfortunately the problem persists on another computer with windows 7 SP1 avast version 2015.10.2.2218.When the computer updated the definitions version 210904-2 the cpu goes up 25% and never goes down.If I boot again it is ok until the next boot.
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Process C:\Program Files (x86)\PC Checkup\SymcPCCULaunchSvc.exe [1972]
Process C:\Program Files (x86)\Norton PC Checkup\Engine\2.0.13.11\ccSvcHst.exe [2036]
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Service Norton PC Checkup Application Launcher [C:\Program Files (x86)\PC Checkup\SymcPCCULaunchSvc.exe]
No there is no residue of old security software installed because I always had only Avast installed.I never used another security software…Keep in mind that before August 25 it was going ok.
That’s not what your log says…Norton PC checkup (which is a security software) was certainly automatically installed with your “TOSHIBA” even if you did not install it personally. https://en.wikipedia.org/wiki/Norton_PC_Checkup
This software was also installed on Toshiba Windows 7 laptops under the name of Toshiba Security Dashboard.
Keep in mind that before August 25 it was going ok.
One does not prevent the other. On August 25, you had a VPS update and it is possible that it integrates (only now) a detection which slows down your PC (Norton or others).
However, I am not competent to assure you that this is the source of your problem (see with gmer for that), I was only pointing out that Norton PC checkup was present on your hard disk
Iam very sorry Chris.It is true when I bought toshiba notebook a long time ago it came with norton but since I started to use the notebook for the first time I uninstalled it and began to use Avast.That was the reason tha I didnt remember, I forgot it.The important thing is that thanks to gmer now goes well and the problem was solved
I just updated Avast virus definitions to version 210906-0 today on my machine and everything is runnning fine, no more problem with high CPU usage.
I would like to take the opportunity here to thank everybody on the forum from the posts’ input contributors to the wonderful Avast software team that make this happened.
Today appears the same problem the cpu stucks on 25% with the Avast Service when it makes the antirootkit scan. I will be grateful if yoy help me. The problem appears on Windows 7 with previous version of Avast.
Now I tested again and is ok.I will test again tomorrow.
