Unable to install Avast

Hello everyone,

I am using Avast Free Antivirus.
Today I have noticed that my UI cannot be displayed. Whenever I clicked it, it popped up for a fraction of a second and disappeared. I decided to Uninstall the whole thing and install it again.

Now when I try to run Installer (both online and offline) it shows me an error “avast installer cannot continue because the last avast operation was performed without restarting”. I ofcourse did restart it after uninstalling.

I also tried to use Avast Cleanup Tool, it did not help.

I am using Windows 10 and Comodo Firewall (I also tried doing it all with Comodo turned off).

What can I do more?

https://forum.avast.com/index.php?topic=232641.msg1538338#msg1538338
https://forum.avast.com/index.php?topic=232823.msg1539425#msg1539425