My problem has been resolved. Thanx to malwarebytes.
For forumers info, this problem started when I downloaded one tiny file named : ae5fe.pdf from nowhere (actually this file came up and I thought this was free marketing report. What a fool!
). When I clicked it, annoying alert windows started to popup. You can check it here:
(sorry..I'm newcomer. You have to add http://www. before adds)
To solve it I download Malwarebytes free version(from another PC) and burn into cd and run it into my infected notebook and it should be ok.
(Note: You cannot download from infected computer because this trojan will prevent you from internet access).
Moral of the story -don't download unknown file!!
Anyway thanx to all and good luck.