|ISP techs always try passing the buck when it comes to problems.|
Open IE and click on tools/internet options/connections and then uncheck 'Use Proxy server'
Then close IE and open it again and you should be able to get back online.
Then I would suggest you do a full scan with Malwarebytes and fix all it finds.
Some HELP in posting on Computing.net plus free progs and instructions 7 Medals