FireFox will never ask you if you want to install a file which you are trying to download.
It'll only do this for browser add ons and extensions.
To fix your problem and see what is going on, open FireFox then in the menu bar, selectTools > Options
You'll then want to select the General
Then half way down the dialog window where it says Downloads
, make sure the first box
is checked Show the Downloads window when downloading a file
Next, select Always ask me where to save files
Now click Ok
From now on when you down load files, you'll see the downloads window and it'll ask you
where to save the file. This way, you'll always know where you're files are downloaded to.
Here is the Google Earth Download page
It's possible that your Anti-Virus program might be deleting the Google Earth download file
(the installer package). So you'll want to pay close attention to what happens when you
But as mi1ez
has said, it's most probably in your downloads folder.
Another thing, when you right click on the file and select properties, you'll probably see
Near the bottom right of the dialog window a button which says Unblock
, you "might"
need to click this button.