I did not do an install, it came to me in an update and I was unaware of the new features until I could no longer use my machine. This also left me at a loss as to what happened to make it so dead. I tried shutting off the three filters to no avail. There ( I thought ) used to be a way to shut it off entirely, but that feature is no longer available.
When you told me to go to "tools" I did not see the Home Network Security, but I found it in the settings/menu icon which opens to yet another menu which does include it. There is no way that I found to turn off all of the tools.
My current system is a fairly hot XP system and I have two other Win 7 4 core systems (much lower power usage and nothing that I have uses more than 1 core) and a Win 10 4 core system all with 8Gb and room for 8 more. They all ran Avast, as does my wife's system, soon to be a Win 10 4 core 8Gb. In order to use this system, I had to download another antivirus (Avira), uninstall Avast, and install the other antivirus. The new software has more adjustments, uses much less system resources, and my machine is now usable.
I fear that Avast has gone to be too user friendly and thus made it unusable. I have been using Avast for many years and have recommended it to many people. I cannot figure out what happened to them.
Thanks for helping me find a way to get this machine running. It is my old clunker, which has nearly everything that I need on it. It has RAID and an Ultrium tape backup system. New things can go bump in the night, but this one is considered "life support" equipment to me. LOL