Need help my computer has a virus i can't get rid off

hey guys i need some help. i think my computer is infectd with a virus or spyware or whatever. i cannot copy and paste anymore. even in word or notepad or any file that i wanna move. i just noticed it today. i tried to type somethingin notepad and pasted it on the same document and this message appeared “have you seen my new Myspace http://122.2.69.49” this message always appear everytime i click paste or press ctrl+V. it ignores the thing the thing that im copying. my anti virus is not detecting anything. it’s always updating everyday. by the way im using trend micro pc-cillin. help how can i get rid of this.