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OK I have looked at the tutorials. I have downloaded the program as instructed. When i try to run the application, it opens and tells me to click next to install software. I then get an error message that tells me that a "previous mapsource not found- setup will terminate"  I am running windows xp on my laptop.  How can i get a free mapsource when it tells me a previous source not found.  Can anyone help me please??