My operating system is Windows 7 64-bit.
Of course, I used Uninstaller Tool in Safe Mode and rebooted system after that.
Yes, I got license keys from Avast and no one of them is suitable (not this one C34471664H1200A0716-BXC2HR03
not this C34470595H1200A0716-AYVEA2D3).

I’m not a newbie, I use Avast for 5 years and didn’t have any problems with renewing license.

Once again I wanna pay your attention to the fact that I tried to activate Avast on a fresh installation of Windows 7 64-bit on my friend’s computer and got the same problem.