Inability to install Bitdefender Online to Windows

Hello all, & forgive me if post is at irrelevant place but I just logged in here.

I found today that bitdefender (bdagent.exe) has been not running (& probably partially uninstalled) at my device for unknown reason & period of time. I tried to uninstall, delete Program Files' bitdefender folders & re-install from previous intallation file & new one, but process is stuck after 1st page where "Preparing Bitdefender Installation" is displayed (pop-up disappears). Tried also to install from Central - same problem. I'm running Windows 10. Any suggestions on the problem?

Thank you in advance.

Andaris