Please help!!! URGENT

Dear web masters, Two weeks ago copy appeared at the base of my Internet Explorer Browser page.  It shut it down and could not correct itself!  I had to shut down my computer and have had to use Firefox.   Some of the copy indicates it may come from you or from someone using your programs or servers.  The only download I had uninstalled was Constant Guard from Comcast.  Microsoft was unable to remotely connect to my computer.  PLEASE, IF YOU KNOW, TELL ME HOW TO GET THIS OUT OF MY COMPUTER SO I CAN DO MY WORK.  I am 82 years old and legally blind.  I have years of experience but this is not in my knowledge base.  Thank you!  Margaret M. Paul  301 654-6468
mmpaul@comcast.net