I have been using the 'much loved' mcafee for a couple of years now as I have never experienced the problems others have described. I have had this subscription for about half a year and it has been fine, then randomly it has started constantly 'Checking for Updates' and running a full computer scan hogging all my CPU.
It completely ignores any sort of schedule and the updates continue even if I turn them off.
The slider appears repeatedly saying the Web Scanner has changed since it was last granted access and though granting access is always a one click procedure, this update causes the slider to appear again and again, before finally accepting it. permissions are set to "Allow full access" through the firewall. The misbehaviour has not occurred again to-day, after the data base update I mean, but I`ll see what happens with the next one and post back. It is not so much that the folder avast4\setup exists, but the file, avast.setup it is only recently that it has become a permanent file, previously it was created for the update and on completion of the update it was removed.
I didn't find much of this problem when I looked it up, but someone did say that it is possible that a virus has attached itself to my mcafee. I uninstalled it and reinstalled it and that didn't help.
If this continues I will remove mcafee and get some free software.
Let it go through the full computer scan and then see if the problem disappears.
I've had Windows Defender in Windows 10 do that constantly scanning thing and the vast majority of the time, it is doing that because it has detected something and wants to remove/quarantine it.
My reccomendation would be to totally uninstall Mc Afee, and install one of the GOOD free ones.