Ok, I'm back, but not because I went to sleep, because I couldn't even open IE! to reply.
I tried boot scan ( 3 times!) and since it took a while... but nothing, still there.
I tried also to running on safe mode, system restore off and nothing
also I couldn't run disk clean up until I uninstall and install back avast, then I could
run disk clean up, but nothing yet.
I will try installing your recommendation of Malwarebytes Anti-Malware.
I'll let you know results
Thanks to everybody!