The Trojan.ISTbar is a Trojan virus that has been spreading on the Internet Explorer web browser.  The Trojan was supposedly created by a company that is called Integrated Search Technologies.  I chose not to link to them out of disapproval of what their company does.  The toolbar redirects Internet searches and adds a bunch of adware to PCs. Sometimes getting rid of the Trojan.ISTbar is as easy as running Windows Defender, but if you do not have Internet access – there are other ways of deleting the Trojan.