Delete and Backspace keys do not delete highlighted text

I am having problems with  my delete and backspace key. Whenever I try to highlight a word or sentence and then try to delete it using backspace or delete it does not work. This occurs in software like internet explorer and MS Office programs. I tried turning on and off the option to replace typing in word and sometimes it works once. I just got my xps16 this month. Not having the problem on any of my other computers.