You may also experience a popup that says "unable to connect to servers" or if it finally does come up and you zoom down everything is fuzzy (no detail).
Do this (on Windows):
1. click on Start (Windows Icon on lower left corner)
2. In the Search box enter "Internet" (without the quotes)
3. click on "internet options"
4. click on "connections"
5. click on LAN settings
6. uncheck "Automatically detect settings"
7. restart Google Earth