Error added: 2014-05-16T11:58:35Z
It may be an issue with a Firefox extension. See https://support.mozilla.org/en-US/questions/837203 I got the same error message, but then tried it on a different machine, and it worked fine. (This page, http://www.oracle.com/technetwork/java/javase/downloads/java-se-binaries-checksum-1956892.html, lists the MD5 checksums of the downloads, so you can check that they match too.)
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