could you tell anyone the different between kmz and kml ?
KMZ is KML-Zipped. It is the compressed version of the KML file.
For further details, check http://www.gearthblog.com/blog/archives/2005/09/google_earth_fi.html
and it can be converted simply The specified item was not found.
To add to what others have said, ArcMap seems to be able to handle KMLs the same way it handles KMZs. I like Dan's approach to unzipping a KMZ using Python, but you can also just open the KMZ in winzip or any other zip program to uncompress it (like 7-zip).
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