The same python script that also unlocked Kindle Books?
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Well, I see a google search returns a 2009 result from cabbage's blog about needing specific versions of Kindle4PC. I apologize for the mistake.
However, let it be known that those problems no longer exist. Also, if one happens to own a hardware Kindle it doesn't seem there was ever a problem with that.
Adding Amazon to your sources today shouldn't cause any troubles whatsoever. It's very easy to tool.