solution Rated 5 out of 5 stars

Did you delete the installed one? it's necessary!I
http://www.mediafire.com/download.php?5a7v7labykaohd3 .
For FF 20, do the same, delete and reinstall!
And if, like me, you don't like the new download manager, open "about:config" and put "TRUE" to "browser.download.useToolkitUI"

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