It's called spyware.
Go to Google or search engine of your choice, type in phrases like "spyware removal" and even "dupe heck removal" and follow instructions found on a search result page.
Then stop using Internet Explorer as a web browser to keep this from happening again. With default settings, it's possible for this sort of garbage to be installed on your system without a single notice to you. Get a copy of Mozilla or Opera as a replacement, and only use IE for Windows Update -- which you are visiting at least monthly right -- and Windows Update alone.
Haven't got a clue what it is or how it's found its way onto my computer but I've got this toolbar which keeps appearing. Even when I go into the View Toolbars and uncheck Dupe Heck Base it still keeps reappearing for a while.
I have done a search to see if I can locate it with a view to deletion but it's not finding anything.
Can anyone tell me what to do to get rid once and for all? Any help much appreciated. Thanks.