After installing Symantec Endpoint Protection 11.0, you see a pop-up saying '[SID: 21631] Alexa User Info Tracking detected.'
Users receive these pop-ups and events when they install Alexa Toolbar on their Internet Explorer or Alexa Sparky (or SearchStatus, etc.) plug-in to Mozilla Firefox. Alexa toolbars are recognized Trackwares (named as Trackware.Alexa) by Symantec Security Response. They gather Internet browsing and search information and submit this information to Alexa.