Hi all,
My question is the one referred on the subject.
I’ve installed avast yesterday on my computer and during the installation I was not prompted to choose whether I need scanning every time my computer boots.
Searching on the menu afterwards, I couldn’ tf ind the necessary button to disable this.
Any ideas?
Thanks in advance,
M.
The boot-time scan doesn’t occur on every boot - only on the subsequent one (unless you schedule it again manually).
Welcome to the forums, Morki. 
When you first install avast, it will want to do an initial boot scan to make sure your computer is clean. Let this first boot scan finish and then it should not bother you again unless, as Igor stated, you manually schedule a boot scan.