Firing Blanks

I am unable to access parts of certain sites. When hitting a link I either receive a blank page or nothing happens! The same happens when I try and open Windows media player or Help and Support.

I often get the following box displayed on my bottom bar " http://xadsj_o.offeropimizer.com" Could this be part of the problem ?

Any suggestions ?

HJT log in the corresponding forum, someone should help you