I am a longtime Avast user (since October 2005, back in its 4.8 days) and recently came across an issue, regarding Avast 10.4 (Build 2233) on my custom built desktop computer.
Operating System: Windows XP Professional (version 2002), with Service Pack 3 installed
Processor: AMD Athlon (XP 2600) @2.08 GHz (Single Core as it predates any multi-core processors)
1.98 GB RAM
160 GB Maxtor Hard Drive
American Megatrends Motherboard
The issue at hand is that AvastSvc.exe uses up my machine's entire CPU (clocked at 100%) and resources, crippling my machine, disallowing me to do anything on it, when running Windows, normally.
I've tried adding the two lines (seen below) to WebShield.ini, which solved my problem in one boot, but AvastSvc.exe spiked my CPU usage and resources on the next boot.
[General]
UseStreamFilter=0
On occasions where it wasn't spiking my CPU usage to 100%, AvastSvc.exe caused Skype to become unresponsive, and ultimately crash. I use Skype to communicate with friends, and associates of mine, and AvastSvc.exe became a detriment to Skype.
My only solution, currently was to roll back to a previous version because even the 2016 Beta has caused my desktop's CPU usage and resources to spike at 100% on boot-up.
This problem began, shortly on early Saturday, October 17, 2015, and I assumed that my computer experienced a surge, or it was infected, neither of which were the case as I scanned my machine with AVG Antivirus 2015, before installing a previous version of Avast.