Avast Free Antivirus Slowing Down PC Performance

Hi everyone,

I’ve been using Avast Free Antivirus for a while now and I’m generally happy with it. However, I’ve recently noticed that my computer has been running significantly slower than usual. It takes longer for programs to open and startup times have increased as well.

I’ve been monitoring my system resource usage and it seems like Avast is consuming a high amount of CPU and memory usage, especially during scans. I’ve tried adjusting the scan settings to schedule them for off-peak hours, but the slowdowns still persist.

I was wondering if this is a common issue with Avast Free Antivirus? Are there any settings or configurations I can adjust to minimize the performance impact?

Avast Free 25.1.9816a (build 25.1.9816.762)

Similar problem since about two weeks [about when I last updated the initial installation - I have since uninstalled / reinstalled (see below)] with ridiculously slow startup and noticeably slower opening of programs. Note that I have Avast on 3 computers and this is happening only on one.

I’m not seeing high CPU usage, but ridiculously long wait to reach login, and then the computer remains all but unusable until Avast’s “icarus” executable finishes whatever it does. Once icarus finishes, the computer is usable but program opening is slower.

The total time from power-on to usable is now averaging 3…4 minutes … if WiFi doesn’t connect automagically and I have to wait for the toolbar so as to do it manually, the time until the computer is usable can be over 6 minutes.

I have checked the hardware, the disk, and the OS [Windows 10, up to date, and no issues per SFC].

I uninstalled Avast and confirmed that the computer behaved normally afterward. Reinstalling Avast again caused the slow startup and slow program opening to return.