Re-download them again. The files are fine, like I said. I've downloaded them several times. Also make sure you're not using the beta version of 7-Zip, use the 4.42 stable.
How big are the files you've downloaded? Because it's more than likely that it's cut out the download and said "it's finished" when it actually hasn't. So I re-iterate my first point: Use a download manager.
Everyone knows that million-to-one chances happen 9 times out of 10; indeed, it's a common requirement in fairy tales. If the human didn't have to overcome huge odds, what would be the
point? Terry Pratchett - The Science Of Discworld
GPGSL S5 Race driver for IED.