...But then, I don’t use AVAST! ...
Annoying that MS forces you to reenter your password and pin as if it were a brand new installation. I had to look it up and of course it defaults to the pin or your MS user name and not your local user account name. No, I don't want to use my MS account name on my local network.
Also, you might have to remove some software to allow the update to go forward. I had to delete some software on my son's computer.
AVG went cuckoo lately too. It turned off and messed up drivers. I had to switch to Malwarebytes.