Switch to mozilla firefox, download, then go to their page and get the noscript or adblocker. Not only is it alot more powerful, but it works trust me I used to have that problem with Internet Explorer too.
Also, it might be because you have adware or viruses on your computer I advise an immediate download of SuperAntiVirus and clean up your whole computer with a full scale scan. (Make sure to update the software regularly and it's free).
Hope my answer helps