When i try to launch the installer it immediatley ends without any warning/message.
Just updated Avast free to newest version and of course rebooted.
Also donwloaded a fresh installer - no effect.
Any idea?
Well, are you getting the installer executable from here? https://www.avast.com/secure-browser
(If you are using an installer for Avast SafeZone Browser and running that, an abrupt termination is to be expected, as Avast stopped supporting ASZB some time ago. ASZB is not supported.)
Are you online and connected when you run the stub installer for ASB? Did you ever run other antiviruses other than Avast?