suspicious update request
Yesterday or the day before I got a surprising alert that I've never seen before. Initially I ignored it because I was busy, but then I got suspicious.
It says, "Google Earth Helper was unable to update," or something similar. I decided that this alert was bogus, so I deleted Google Earth and the matching folder in Applications Support. The alert continues to display intermittently. How can I find out what this is, and eliminate it?
MacBook Pro, OS X El Capitan (10.11), 3 GHz core duo, 8GB RAM