This seems to bear repeating.
If you've got the Google Earth Extension loaded into Civil 3D and you install SP2, you WILL GET ERRORS. Now, before you start whining and complaining about how bad Autodesk sucks, uninstall the GE Extension and get on with life.
I mean, c'mon. Who's REALLY using GE right now, and will the continued functionality of that overrule the functionality of SP2?