Endpoint Protection

We just upped our Norton renewal about a month ago, and this week started receiving problems with IE.  Search terms in google and yahoo are frequently redirected to random websites and our laptop seems to be running slower on response times.  Also getting random AV threats popping up through the internet browser.  I have ran several scans, which come back as all clear.  I also did a system restore to 3 days ago, but that hasn't helped.  Not sure what to try next. 

use process explorer and see which suspected process are running and try closing them. and observer.
 
you canuse loadpoint diagnostic utility to check if any suspected things are loaded onto memory and upload it to security response to further analysys

 check if you find some unnecessary processes running in the task manager if yes submit those files.

Make sure you have the latest definitions. Sometimes antivirus software fails to remove viruses in "normal mode" so the best thing is reboot to Safe-mode and perform a full scan.