It has been my understanding that the pre-boot scan has to be scheduled using the Avast GUI. With an infected machine it is often impossible to invoke the GUI because of the virus. In fact, some viruses purposely inactivate the AV program to more easily do their dirty work. Thus the necessity of having an .EXE to get an Avast GUI after booting to safe mode. Then schedule the scan, reboot and let Avast do its thing. If I am missing something or there is another way of scheduling a pre-boot scan on an infected machine, please enlighten me. I’ll be the first to admit that after 40 years working with data processing, I still have a lot to learn.

Thanks so much TECH for your contributions, I’m sure a lot of users learn from them.