Can't update Avast, receive message "invalid file signature"

Received notice from avast that I need to upgrade but when I try I get the message “invalid file signature”. I’ve tried all day with no success.

thanks

Please post in the correct forum next time.
This one is about the https://my.avast.com website.

https://forum.avast.com/index.php?topic=181035.msg1280278#msg1280278

Supposedly resolved, response from an avast team member: