My Avast Free won’t update the program or the virus definitions. I would like to re-install but I can’t turn off Avast
Did you just install avast?
did you remove previous used AV before installing avast?
Avast removal tool https://www.avast.com/uninstall-utility
General: Uninstalling a third-party antivirus software https://www.avast.com/faq.php?article=AVKB11#artTitle
I have had it for probably two years
Hi jedandthelma 
Try a clean install :
Download the Avast! Uninstall Utility to your desktop.
Download the correct version of Avast!
Avast! Free
Avast! Pro
Avast! Internet Security
Avast! Premier
Disconnect from the internet.
Uninstall Avast! via control panel.
Run the Uninstall Utility and accept the reboot to safe mode.
Once complete reboot your system.
Reinstall Avast!
Greetz, Red.
I have tried to unintall Avast via the control panel, but it won’t allow me to as long as Avast is running.
And I am unable to turn it off. I can’t even kill it in the Task Manager
And when you run the Avast! Uninstall Utility ?
Greetz, Red.
I have not tried that. I was under the understanding that you had to run uninstall from the control panel before running the Avast utility
And what does the instructions say …
Sometimes it's not possible to uninstall Avast the standard way - using the ADD/REMOVE PROGRAMS in control panel.[b] In this case, you can use our uninstallation utility avastclear.[/b]
The reason for rebooting into safe mode is that you are assured the low level drivers are “not” running
making the uninstall complete.
I am unable to update virus definitions also - keep being told I have to reboot then I try again to do the update and again told to reboot. HELP SOMEONE - thanks
Hi nelliepurrbear, welcome to the forum
Can you please start your own topic ?
Because helping two ( or more ) people in the same topic will lead to confusion.
Greetz, Red.